Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-29-2010, 08:58 AM   #16
Forum Member




Join Date: Dec 2009
Photos: Gallery
Posts: 94
Original Poster
QuoteOriginally posted by aleonx3 Quote
I don't quite follow your logic here. The FA Limited lens design was done some years ago, and because of the precision in the lens design, they can only make so many per year. Meanwhile, the demand for these lens are still there worldwide. The R&D on these lenses have been spent years ago. Should Pentax stop the production of these FA limited lenses just because there is another lens similar to these? or should they stop make DA limited 35 macro (which is a new design) and get out of the business completely.

The logic you imply is that if they don't follow the two leaders in the market, they will be doomed - I think not. It is important that their strategy continue to "be interesting" and appeals to people who know the good from the average. Just look the K-7 body design alone, how many C-models that share more or less the bodies... 20D, 30D, 40D, 50D, 7D and 5D... and counting....
I agree very much with your remarks, aleonx. However there are many ways to "be interesting"! You may go like CitroŽn did (see my small anecdote), but it is dangerous -- and some of the clever 'features' offered today by Pentax remind me CitroŽn in some way. You may however do 1000 other things that would be more 'rational'. Following the two leaders would be stupid, for one, that's clear.
Suppose you would cut, let's say, 2 lenses of today's lens line up among the redundant ones. With equal production means, you would have room for two new lenses! How about a long, fast tele? How about ...fill in here... ? How much more business Pentax would do?

04-29-2010, 10:19 AM   #17
Pentaxian
aleonx3's Avatar

Join Date: Jul 2007
Location: Brampton, Ontario
Photos: Gallery | Albums
Posts: 3,888
QuoteOriginally posted by danielausparis Quote
I agree very much with your remarks, aleonx. However there are many ways to "be interesting"! You may go like CitroŽn did (see my small anecdote), but it is dangerous -- and some of the clever 'features' offered today by Pentax remind me CitroŽn in some way. You may however do 1000 other things that would be more 'rational'. Following the two leaders would be stupid, for one, that's clear.
Suppose you would cut, let's say, 2 lenses of today's lens line up among the redundant ones. With equal production means, you would have room for two new lenses! How about a long, fast tele? How about ...fill in here... ? How much more business Pentax would do?
Danielausparis, I understand your concern with examples like Citroen... however, I view this as slightly different.... since it is the japanese company - using the similar example as Subaru vs the auto-giants like Honda and Toyota. They are still around after many years and don't seem to fade away anytime sooner than the North American car companies. Going back to the DSLR market, I can see two completely different strategies played by the companies (SONY and Pentax) trying to catch up with the big two. If only Pentax will come out with FF lineup in the near future you will be able to tell which strategy will be more successful - time will tell.
04-29-2010, 04:55 PM   #18
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
QuoteOriginally posted by danielausparis Quote
And yes, looking at the DA's, FA's etc. it seems they have been developed by entirely different teams, with different objectives in mind etc.
Sounds good to me. I fail to see what is wrong with this, or what is even different from all the other major manufacturers.

QuoteOriginally posted by danielausparis Quote
I complain, because you have a redundancy there. I'm not saying that these lenses aren't excellent!
There is no redundancy if the lenses are good at different things. What Pentax are giving us is choice, which most would see as a good thing.

QuoteOriginally posted by danielausparis Quote
Let me tell a small anecdote
The only thing I hate more than cars is car analogies. They are completely arbitrary.

QuoteOriginally posted by danielausparis Quote
And yes, extending this offer towards the high end market would mean, in my view, to propose a full frame. But of course, Pentax could decide to not meet the high end market, as they have done so far.
Heard about the 645D? Talk about kicking full-frame butt!
04-29-2010, 10:41 PM   #19
Forum Member




Join Date: Dec 2009
Photos: Gallery
Posts: 94
Original Poster
QuoteOriginally posted by rparmar Quote
Sounds good to me. I fail to see what is wrong with this, or what is even different from all the other major manufacturers.
There is no redundancy if the lenses are good at different things. What Pentax are giving us is choice, which most would see as a good thing.
Agreed, it would be nice in a world where there would be an infinite amount of production means and R&D $$. In the real world however, this just sacrifices really necessary, additional lenses to fill concrete gaps or missing links.

QuoteOriginally posted by rparmar Quote
Heard about the 645D? Talk about kicking full-frame butt!
Yes I heard about it, especially its price point that will confine it to pros having already a nice stock of 645 lens capital, or oil sheikhs / russian millionaires

04-30-2010, 05:00 AM   #20
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
QuoteOriginally posted by danielausparis Quote
In the real world however, this just sacrifices really necessary, additional lenses to fill concrete gaps or missing links.
Wonder why you think so. Perhaps the DA35 was easier and cheaper for Pentax to produce? Certainly the DFA 100mm was, as all they had to do was re-use an existing optical design and update it with weather seals. Pentax are very good at working with their strengths and building on them.

QuoteOriginally posted by danielausparis Quote
Yes I heard about it, especially its price point that will confine it to pros having already a nice stock of 645 lens capital, or oil sheikhs / russian millionaires
It's not that expensive. In fact it's well cheaper than all the other MF digitals and represents a bargain. Here in Europe it's not much more than a pro full-frame (if projected price of 7K euro is true). And of course it will drop in price once established in the market.
04-30-2010, 08:31 AM   #21
Forum Member




Join Date: Dec 2009
Photos: Gallery
Posts: 94
Original Poster
QuoteOriginally posted by rparmar Quote
Wonder why you think so.
Robin, this is pure logic and not, for once, my own ponderings... Imagine available production means as a set of slots (100%). Your product portfolio maps slots to product A, product B, etc. You have (sum of all slots) = 100% = total product ouput.
To me the situation is like having not an even distribution of distinct products A, B, C,... Z, but more like having A, A', A'', B, B', C, C', ... consuming slots with redundant products. Since in my analogy slots cannot extend, you cannot introduce new products without sacrificing other ones. In other terms, today's gaps in the lens line up could easily be accounted for just by optimizing the portfolio with respect to redundancy.

Of course in real life, slots are extensible thanks to risk capitalism. However, before going to be invested, capital will think twice, and check if there are not already potentially available slots...

QuoteOriginally posted by rparmar Quote
It's not that expensive. In fact it's well cheaper than all the other MF digitals and represents a bargain. Here in Europe it's not much more than a pro full-frame (if projected price of 7K euro is true). And of course it will drop in price once established in the market.
I just had a look at competition (Hasselblad) and nearly collapsed You are correct, the 645D is a bargain!
04-30-2010, 09:41 AM   #22
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
Your production analysis does not take into account factors similar to those I already mentioned: leveraging past investments for example. Also, you assume all of these lenses were produced at once to fill fixed slots, which they certainly were not. They were produced over time to meet changing needs in the market. While there are some gaps in the line-up, Pentax has done quite well for a small player, with everything from 10-600mm covered.

The big omissions:
* teleconverter
* tilt/shift lens, or at least a mount to use existing 645 lenses for this purpose
* fast inexpensive normal
04-30-2010, 09:47 AM   #23
Veteran Member




Join Date: Apr 2008
Location: Minnesota
Photos: Gallery
Posts: 1,530
QuoteOriginally posted by rparmar Quote
Your production analysis does not take into account factors similar to those I already mentioned: leveraging past investments for example.
I agree with your points Robin. However I just wanted to add that when reading this QFD, Kano Analysis and KJ Methodology exercises ran through my head.... stupid Six Sigma training

04-30-2010, 10:14 AM   #24
Forum Member




Join Date: Dec 2009
Photos: Gallery
Posts: 94
Original Poster
QuoteOriginally posted by rparmar Quote
Your production analysis does not take into account factors similar to those I already mentioned: leveraging past investments for example. Also, you assume all of these lenses were produced at once to fill fixed slots, which they certainly were not. They were produced over time to meet changing needs in the market. While there are some gaps in the line-up, Pentax has done quite well for a small player, with everything from 10-600mm covered.

The big omissions:
* teleconverter
* tilt/shift lens, or at least a mount to use existing 645 lenses for this purpose
* fast inexpensive normal
Correct, the explanation over-simplified things. And yes, Pentax did a good job -- please note that the longest tele is the DA* 4/300 -- but we all may see some weaknesses both in some technical choices (what I called "bling-bling") and on the portfolio itself. That was the initial subject of this discussion!
And each of us could produce a nice wishlist... Could be matter for a new thread :-). The point is that keeping the current portfolio as is probably completely obliterates any possibilities of extensions... Isn't it?
04-30-2010, 01:08 PM   #25
Senior Member




Join Date: May 2008
Location: Victoria, Australia
Posts: 212
QuoteOriginally posted by danielausparis Quote
please note that the longest tele is the DA* 4/300
The longest telephoto, by custom order only, is still the Pentax FA* 600mm F4 ED(IF).

whilst i'm here preparing for a Zombie Shuffle...

QuoteOriginally posted by danielausparis Quote
1. Lens portfolio. Pentax offers today not less than 5 (five) isolated lens families.
how are they isolated? They're all K-mount derivatives. it's one thing to say the new FA645 55mm SDM won't fit on a K7, but there's nothing stopping you from mounting any of the K-mount lenses on a current Crop KAF3 camera

QuoteOriginally posted by danielausparis Quote
One may wonder. Does this correspond to 5 isolated teams within this company, competing one against the other?
It would be pretty silly to have 2 teams tasked to develop the D-FA and FA line, given that there hasn't been a new FA design since the FA31mm LTD in 03, and the D-FA 100mm Macro WR is (as far as my research says) the same optical formula as in the non-WR D-FA macro, as well as the FA macro and F macro.

Again, they're not isolated and if anything, the majority of FA lenses were developed well before Pentax even thought of the MZ-D, whilst most of the DA lenses were developed after the release of the *ist D in 03.

there's also the note that a lot of Pentax's Digital lenses were co-developed with another company, saving R&D resources. In one case, the DA18-250, Pentax took an existing Tamron lens and rebadged and recased it.

QuoteOriginally posted by danielausparis Quote
Anyway, who can reasonably argue that you need both a 35mm and a 31mm?
will the FA31LTD do Macro? will the DA31 work without vignetting on my Film K1000. Can i afford either when the FA35 F2 is a nice cheap in-between step..

QuoteOriginally posted by danielausparis Quote
a 40mm and a 43mm?
Will the DA40 work fine on my K1000?

QuoteOriginally posted by danielausparis Quote
a 70mm and a 77mm? Etc. etc. Meanwhile, important gaps can be noticed in the portfolio.
and other gaps would be introduced if pentax were to consolidate as per your suggestion.

QuoteOriginally posted by danielausparis Quote
Who cares really about a 35mm being macro?
You don't. others do. I would if i could afford some more lenses since i want a wide angle close focusing lens like the DA35LTD for some of my hobbies.

QuoteOriginally posted by danielausparis Quote
We all know that macro prefers some longer lenses, 90mm and above.
all of which are too look for my macro usage.

QuoteOriginally posted by danielausparis Quote
Of course, there is the D FA 100mm, but autofocus won't be very helpful in macro
... on the assumption that the ONLY thing you're using a D-FA 100mm for is Macro...

the D-FA 100mm is the right size for my portraiture and has nice bokeh imo, but far far too long for my macro work. shame i didn't pick one up when i was in japan...

QuoteOriginally posted by danielausparis Quote
These discussion matters appear everyday in Pentaxforums...
Same with Full Frame discussions. Doesn't mean they're not stupid, banal, and from people who really need to drop K-mount and go to Canon or Nikon...

Yes, i took out "good reason" for a "good reason"

QuoteOriginally posted by danielausparis Quote
2. "Bling bling" syndrome. One has still to explain why one needs Weather Resistant lenses (or bodies).
Sand. Rain. Seasalt, Tomato and Barbeque sauce. Fake blood. I've seen Canons and Nikons die in the same usage i put my K200D and K7 though. And i've seen people not take their cameras in similar situations.

QuoteOriginally posted by danielausparis Quote
Durability? Please, show me these lenses and bodies in 40+ years (age of my K and M lenses, that are like new).
there's no doubting that the current lenses won't last as long as, say, an M lens (hell, my Tamron 18-200's falling apart...), but i would want it to fall apart later, given the abuse i give my cameras and lenses and the conditions that it goes through, rather than some similarly priced DSLR or lenses that isn't build as strongly.

QuoteOriginally posted by danielausparis Quote
Why do I need to spend real money for a feature that is not at all my (or anybody's) requirement?
Where is the assumption that having WR adds significantly to the cost? to get K7 kind of sealing with Canon or Nikon, you're looking no less than the 1D and D3 series. On it's own, the 18-55WR and 50-200WR aren't significantly more expensive. Sure, the DA*s are fairly expensive as Pentax lenses go, but they're no more expensive than equivalent Canon Ls and Nikon pro lenses.

Don't make the assumption that WR isn't anybody's requirement. It was one of mine, and one of the reason i stayed with a K200D and instead of moving to the 450D & D60. It's the reason i stayed with the K7 instead of moving to a D90 or 50D

QuoteOriginally posted by danielausparis Quote
Same question, even more serious one, for SDM: why the heck spend top dollar for a feature that is already taken in charge by the body? This looks again like competing isolated teams developing redundant solutions for problems that don't exist. I prefer not to discuss the SDM disaster here, it has already been subject to many posts and initiatives elsewhere.
Admittedly, Pentax's SDM implementation in-lens leaves a lot to be desired. But the contacts are already there (they are old Power Zoom contacts). why not use them for something?

however, the problem did exist. the speed of the screwdrive AF, pre K20/200D generation, wasn't exactly brilliant. It was also noisy. Sure, the SDM isn't Canon L USM silent, but it was a damn sight better than anything on screwdrive.

a full move to SDM can't happen as Pentax's DA LTD pancake lenses don't have the physical space to have one. If pentax can implement a ring type USM motor like in Canon's USM or Nikon's AF-S, then SDM on K-mount becomes decidely more appealing. My friends with Sigma HSM lenses on their Pentax DSLRs dont' seem to complain....

you're also saying this as if no other company has ever had to decide on whether to put AF motors in the body or lens...

QuoteOriginally posted by danielausparis Quote
3. Bodies. Meanwhile, there are today only two bodies to choose from.
So? 2 good, well segmented bodies isn't a bad thing...

QuoteOriginally posted by danielausparis Quote
Canon has nine...
with 4, yes, FOUR, in the entry level bracket. all varying so little that video and price point is the segmentation.

QuoteOriginally posted by danielausparis Quote
Nikon has nine as well.
i count 7 (D3000, D5000, D90, D300s. D700, D3S, D3X) and Again, all so close that they overlap.

QuoteOriginally posted by danielausparis Quote
Everything speaks for a reach towards high-end markets, since low and middle are already covered. Such a camera could have been developed a long time ago with the engineers of the WR and SDM teams -- at no further R&D expense.
*points to the 645D* It's a high end market that Canon or Nikon don't have campers high-end enough to compete in.

Realistically, the high end market is small. 5-9% or so. Sure, everyone with a Digital Rebel wants an FF, but how many are actually going to pony up the funds to do so.

for a company so small with such a small sales percentage, there are events i go to that have more Pentaxes than FF cameras from the 3 FF makers combined. and invariably, unless they're pros, if it starts to pour they'll be the first ones under cover protecting their FF bodies..
04-30-2010, 01:24 PM   #26
Pentaxian
bdery's Avatar

Join Date: Mar 2008
Location: Quebec city, Canada
Photos: Gallery
Posts: 5,830
QuoteQuote:
One has still to explain why one needs Weather Resistant lenses (or bodies).
What about shooting in rainy or snowy situations? I've relied on WR plenty of times while others ran to cover their gears.

The 35 mm macro is regarded as one of the best lens ever, and its users positively love it. I see it as a general use prime. Sort of like a high quality "kit prime"...

If the Pentax lineup doesn't suit your needs/style, that's fair. But to me the lineup makes perfect sense.

Pentax also offers a 100 mm macro, you know.
04-30-2010, 02:57 PM   #27
Forum Member




Join Date: Dec 2009
Photos: Gallery
Posts: 94
Original Poster
nakey, bdery, thanks for sharing your thoughts. While I agree with a lot that you argue:
- still get the impression of isolated lens lines designed at different moments, each with its own look-and-feel, probably by different teams, thus lacking consistency to some degree. You like the 35mm macro? So do I. But then, is the 31 really mandatory to keep as well? Even if by doing so, precious production means cannot be invested for a nice new lens that would fill gaps?
- Also, as I said at the beginning, of course I appreciate the optical gems Pentax is offering. It is because I wish the very best for this company that I was reflecting on how to make the line up even more seducing, complete and attractive, given the constraints already mentioned.
04-30-2010, 07:06 PM   #28
Pentaxian
bdery's Avatar

Join Date: Mar 2008
Location: Quebec city, Canada
Photos: Gallery
Posts: 5,830
I think Pentax move in two directions:

1-WR photography

They have amazing stuff for all kinds of shooters : macro, hiking, weddings, sports. A very well blanced line-up which could only be improved with more WR primes

2-Limiteds

Or, in more general terms, small and amazing primes. I just read the review of the Canon 24 mm recently posted at photozone and laughed out loud when seeing the size of that monster. I understand that it's quite fast but just looking at my K20D with 21 mm LTD and then at the picture at photozone makes me smile even now.

Pentax have an excellent linup of small, portable primes that cover a great range. Remember that the "current" lineup is the DA line, the FA lenses are being phased out.

So there you are : WR plus small primes, with of course a few "regular" lenses thrown in (17-70, 55-300). And even those are well positionned (the 55-300, for instance, covers a great range, and is better than what others offer).
04-30-2010, 11:11 PM   #29
Moderator
Site Supporter
Blue's Avatar

Join Date: Jun 2008
Location: Florida Hill Country
Photos: Gallery | Albums
Posts: 17,212
QuoteOriginally posted by danielausparis Quote
Dear friends,

. . .

1. . . . Who cares really about a 35mm being macro? We all know that macro prefers some longer lenses, 90mm and above. Of course, there is the D FA 100mm, but autofocus won't be very helpful in macro. These discussion matters appear everyday in Pentaxforums for good reason.

!
Actually, quite a few people care that the DA 35mm ltd is 1:1 macro. That was a major reason I bought it. I have always had a "normal" lens at the backbone of my macro work for the better part of the past 20 years. And they can be used for insect work. 1:1 is 1:1. Even with a 90-105mm macro, I would still need one in this range. If I were to land an FA* 200mm f4 or A*, I would sell the 105mm in a NYC second but would keep the 35mm macro and the 55mm Macro Tak.

Furthermore, there's nothing wrong with a little 'bling' as long as there's enough horses under the hood. If the DA 35m ltd was car, it would be John Milner's Deuce Coup.

The gaps are at the 105 to 150mm range. They could revise and re-release the FA 135mm f2.8 (maybe redo it as a ltd ) and the 200mm f4 macro and they would have the primes covered.

Robin already mentioned the tc and tilt-shift shortage so I want go any farther with that.
05-01-2010, 04:17 AM   #30
Senior Member




Join Date: May 2008
Location: Victoria, Australia
Posts: 212
QuoteOriginally posted by danielausparis Quote
still get the impression of isolated lens lines designed at different moments,
Because clearly a DA lens designed in the 1990s would make total sense </sarcasm>

As has been said before, there's been no new FA lens since 03. it would be foolish to kepp R&D money on a format they don't intend to take up in the future. all the properly new lenses, whether they're codeveloped with Tokina or Pentax's own designs, are all DAs.

QuoteOriginally posted by danielausparis Quote
each with its own look-and-feel
I hate car analogies. I hate them as much as i do Paedophiles, White Supremacists, Pauline Hanson, Canon Australia, Mac/Linux fanboys, and the XD card. But if i may...

Take the Ford Focus. your standard base model (DA) is simple and utilitarian. Spend a little bit more and you get to the higher spec mode (DA LTDs) with all the mod cons like a metal body or 6 CD surround sound stereo with satnav. then there's a Focus XR5/ST (DA*). Feels totally different in it's handling and performance.

At the end of the day, all 3 models are the same Focus. Just different spec levels.

It's also kinda well known that the current ford Focus is based on the Mazda 3 (FA) not surprising when they're all part of the one big company (Pentax)

And back to cameras, the D-FAs are only rebodied FA macro lenses with a more advanced SMC coat that helps enhance their performance on digital bodies. Just like the change from D-FA to D-FA WR, it's not a significant engineering change, not compared to making a whole new lens like the DA*60-250...

QuoteOriginally posted by danielausparis Quote
probably by different teams
because the chances of the R&D staff in 1980 being exactly the same as the one in 1990, 2000 and 2010 is really high... </sarcasm?>

QuoteOriginally posted by danielausparis Quote
thus lacking consistency to some degree.
They're perfectly consistent based on what lens generation they are. all the Ks look the same. All the Ms look the same. Same for the As, A*s, Fs, FAs, FA LTDs, FA*s. DAs, DA-Ls, DA LTDs, DA WRs, and DA*s. the only except is the D-FAs where the newer D-DA WR looks more like an LTD rather than D-FA.

QuoteOriginally posted by danielausparis Quote
You like the 35mm macro? So do I. But then, is the 31 really mandatory to keep as well?
Again, i ask you. how useful is the DA35's smaller image circle and lack of aperture ring on a K1000? you're also forgetting that the 31LTD's F1.8 is 1 1/3 stop faster than the DA35 macro's F2.8. that is quite a bit of light. and in Film, that extra light is important especially since high ISO films are very grainy, and you can't change your ISO unless you change your film.

on a personal note: there are plenty of instances where i find the FA50mm too long. if i wanted 35mm F2.8, i'd be using my Tamron 17-50 F2.8, and where i'd want the 31LTD, the F2.8 is far too slow either because of bokeh or lack of light. I want the 31LTD because it suites my shooting where the DA35 Macro doesn't. the DA35mm Macro suits my shooting where the 31LTD doesn't.

QuoteOriginally posted by danielausparis Quote
Even if by doing so, precious production means cannot be invested for a nice new lens that would fill gaps?
Gaps based on who's opinion? where i see gaps in the Pentax line, i either see them filled wonderfully by a third party (EG: Sigma's orgasmic 70-200 F2.8 DG HSM and the new CZ based Hartblei super-rotator T/S lenses), or unfilled on any mount (EG: Small, affordable, lightweight, weathersealed superzoom on Crop. the only lens that comes even remotely close is Canon's 28-300L which is neither small, lightweight, or cheap). the spread of currently available primes from 14 mm up to 300mm is well sorted.

QuoteOriginally posted by danielausparis Quote
It is because I wish the very best for this company that I was reflecting on how to make the line up even more seducing, complete and attractive, given the constraints already mentioned.
When Canon shooters are willing to disassemble and modify FA31mm LTDs and A50mm F1.2s to put onto their 5Ds, and when Pentax LTD primes have the reputation of excellence that is unmatched by any save some of the cosina made VL & CZ primes, i don't think we need to make them any more seducing or attractive.

IF i see gaps in the Pentax system, it ain't their bodies OR lenses...
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
bodies, camera, company, course, dslr, feature, lenses, macro, pentax, photography, sdm, teams
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
What's your backup strategy? heliphoto Photographic Technique 133 01-09-2010 09:55 AM
Do you have a unique marketing strategy or technique? MJB DIGITAL Photographic Industry and Professionals 8 03-17-2009 03:11 PM
Need help on lens strategy land65 Pentax SLR Lens Discussion 13 06-01-2008 06:25 PM
Another lens buying strategy thread. Sprags Pentax SLR Lens Discussion 2 02-06-2008 07:48 PM
Translation from PMA Pentax Interview - new DSLR body this year and company strategy Katsura Pentax News and Rumors 66 09-23-2007 04:15 AM



All times are GMT -7. The time now is 05:47 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top