[funkysmurf]

Hi all,

I'm currently using Nikon FF equipment and I must admit that I've only been interested in switching to Pentax when I started reading about the 645D a couple of years ago.

I had the chance to test it out briefly, but the slow image review time and the lack of lenses available at my local dealer put me off a bit, so I kept my D4/D700 and collection of lenses and accessories. Now that the 645Z is a few months away, I'm looking at it as a serious option again as the lens availability will be drastically improved according to my local dealer (not hard since they only had the 645D with a 55mm, and then got rid of Pentax all together...and now they're fully back on board and excited ).

I've had a look at the lens database on this board, and if I'm understanding things correctly, the selection available isn't particularly fast.
My two most used lenses are the 200mm f/2 VR2 and 85mm f/1.4. I absolutely love the 200mm f/2 - it's fast focus, the sharpness, bokeh, colour...everything about it really. I literally make excuses to use it even when a shorter lens would be more practical. Despite its weight and size, I take it with me even when I'm out and about doing street stuff.

So after coming across as wanting to have babies with that thing, my question is...is there anything in the Pentax range that is its equivalent in terms of image quality/sharpness?

What about the 14-24, 24-70 and 70-200mm zooms? From my understanding, after accounting for a .79 crop factor, the best I can get is ~ f/2.2 equivalent with the 90mm F2.8 ED AW SR Macro. The 300mm F4 ED [IF] becomes a 237mm f/3.2 and is apparently not as good as the 300mm F5.6 ED [IF], which translates to about f/4.4.

I welcome any helpful input and in the meanwhile I'll check out the exif of photos posted on the board. Please excuse my ignorance if Pentax lenses are generally much better than anything Nikon has ever produced...as you can tell the Pentax side is very new to me.

Cheers.

[Adam]

I've had a look at the lens database on this board, and if I'm understanding things correctly, the selection available isn't particularly fast.

They aren't any Pentax medium format lenses faster than F2.8 because of size limitations, but since you're basically limited to shooting on a tripod, this isn't a huge drawback. The 645 lens lineup is quite good optically because it's been designed for professionals since the start, though you have to look at the reviews of each individual lens for the pros and cons.

One thing to note is that there are only 3 modern 645 lenses out there: the 25mm, the 55mm, and the 90mm. All the other "new lenses" are from the film era and as such the coatings/AF mechanisms are older.

Generally speaking, the 645 system is designed primarily for studio and landscape use. The new 645Z is definitely going to pack a punch resolution-wise, but if you want to shoot action, telephoto, or just about anything hand-held, APS-C and FF DSLRs are the better choice. So I would say picking up a 645Z and selling off all your other gear would backfire, though it would be a great complement to a D700 or D4 with Nikon's trio of premium zooms for instance.

Here's a link to over 350 sample photos taken with the 645D, with EXIF intact:

PENTAX 645D | Sample Photos for Pentax Cameras & Lenses - PentaxForums.com

[maxfield_photo]

One has to realize that as the size of the format increases, lenses will necessarily become slower. f/2.8 is the "1.4" of medium format, and to take it further f/4 is the "1.4" of 4x5, and f/5.6 is "1.4" of 8x10. If you're shooting film you can counteract the loss in lens speed by shooting on faster film, knowing that you won't need to enlarge your negatives as much to get the same, oh say, 11x14 print. The same is still mostly true for digital, lower noise with larger pixels, more dynamic range, but I will say some of the higher end 35 mil digital camera are beginning to bridge that gap. We'll have to wait and see what the images from the 645Z will look like. I predict insanely good shadow detail.

Perhaps more importantly though, if manufacturers were to construct, say, an f/1.4 for a 4x5 camera, the depth of field would be so shallow when shot wide open as to make just about any image unusable.

Medium format is just a different animal than 35 mil.

[Louicio]

Medium format is just a different animal than 35 mil.

Agreed. funkysmurf, If you are unsure if the format is for you, perhaps you could buy a film 645 and try it out without breaking the bank?

[Uluru]

Different formats, different apertures, different focal lengths, different everything. The MF is a bigger step to our understanding than going from APS-C to FF. Because of the sheer size of its components, and the level of image making control that enables.

It imposes different dynamics of image making, different approach, different philosophy altogether. Results are also very different.

On MF one really needs no faster than f2.8 as the size of glass becomes enormous. But the feeling is same or better than using an f1.4 on FF, and even more control and details and contrasts are captured with an MF lens.

Hard to explain as there are no good analogies. In other words, think of MF as a totally different world, with its own rules and gravity. Forget FF comparisons.

As others suggested, good idea is to try Pentax 645 film camera, or a Pentax 67 film camera, too. Get some film and try to get into the MF world. You can always use all 645 and 67 format lenses on 645Z.

[ElJamoquio]

f/2.8 is the "1.4" of medium format

F/1.4 in FF is equivalent to about F/2.8 in 6x7 film ('medium format')
F/1.4 in FF is equivalent to about F/2.3 in 645 film ('medium format')
F/1.4 in FF is equivalent to about F/1.8 in 645D/Z ('medium format')

It varies quite a bit! 6x9 would be even a bit higher. The OP is correct in that there is no ultra-fast 645 glass in Pentax mount. I'm actually unaware of any 645 glass in any mount that's faster than F/2 (although it probably exists).

---------- Post added 04-21-14 at 11:41 PM ----------

Different formats, different apertures, different focal lengths, different everything. The MF is a bigger step to our understanding than going from APS-C to FF.

Depends on what you're talking about. FF->645D is less. FF->67 is more. See above...^

Now if you're talking about the differences in terms of general use...

[veraikon]

Hi all,
... I've had a look at the lens database on this board, and if I'm understanding things correctly, the selection available isn't particularly fast.
... .

f2.8 in medium format (MF) is fast.
I only know three MF lenses which are faster: two Carl Zeiss Planars (CZ Planar 2.0/80 for Contax 645, FE-Planar 2.0/110mm for Hassy F and the Mamiya 1.9/80mm for Mamiya 645) .

[Ed Hurst]

Next best thing is the Pentax 6x7 105mm f2.4, which can be used on the 645n/nii/D/Z with an adaptor... But the main point IMO, as made above, is that the usage of a larger format is generally somewhat different.

[Uluru]

F/1.4 in FF is equivalent to about F/2.8 in 6x7 film ('medium format')
F/1.4 in FF is equivalent to about F/2.3 in 645 film ('medium format')
F/1.4 in FF is equivalent to about F/1.8 in 645D/Z ('medium format')
...
Depends on what you're talking about. FF->645D is less. FF->67 is more. See above...^

Now if you're talking about the differences in terms of general use...

There is no equivalency of any kind as the image rendering is totally different. Totally. Glass construction renders a totally different quality of light and details.
I mean really, this is no joke. Leave mathematics aside because it explains nothing what is really going on. There is no valid comparison. Aperture alone has nothing to do with it.
The nearest analogy between the detail and overall feel between the MF and FF would be that the 'equivalent' FF image is a colour xerox on paper of an original oil painting made on canvas.

[tlong423]

I used lots of Nikon equipment (35mm and digital) professionally for several years. Good stuff.

Eventually I left Nikon and returned to using Pentax equipment (35mm and APS-C). Better stuff.

And comparing my Pentax 645 stuff to my Pentax 35mm and APS-C -- the 645 blows that away. Best stuff.

[ElJamoquio]

There is no equivalency of any kind as the image rendering is totally different. Totally. Glass construction renders a totally different quality of light and details.
I mean really, this is no joke. Leave mathematics aside because it explains nothing what is really going on. There is no valid comparison. Aperture alone has nothing to do with it.
The nearest analogy between the detail and overall feel between the MF and FF would be that the 'equivalent' FF image is a colour xerox on paper of an original oil painting made on canvas.

With the apprpriate design/coatings/sensors the pics would be indistinguishable.

[pinholecam]

Gotta love PF.
All it needs is a little carrot thrown in (simple not too detailed question) to get forumers to be at their throats arguing big theories.
(Meanwhile, the perpetrator is sitting back eating popcorn)

Sometimes I love the simplicity (and inanity) of the answers one gets on Canikon forums.
"Once you get XXX you won't look back"

The TS is so unclear as to what he's looking for.
Resolution, tonality, low light performance, AF speed?? What?
On the one hand he talks about long fast lenses for shallow DOF type shots (bokeh mentioned)
But on the other, it seems he's talking 14-24, 24-70 (more landscapes, generalist lenses)

TS, you need to state what you shoot so that ppl can help you out.
Furthermore, you seem unclear of what MFD will give you and the workflow it requires (eg. tripod shooting to get the best quality)
Your requirements seem all over the place.
If shallow DOF is the thing you are looking for (and the thought that MFD will get less of it), its the wrong direction imo.
You'd be better served with Brenizer method on your current system or shooting 67 film.

[funkysmurf]

I appreciate everyone's input. I may have been a little unclear with my questions/requirements. I don't have any zoom lenses. When I listed the 3 Nikon zooms, it was a question of how the Pentax side would compare in terms of image quality. Since I rightly or wrongly assumed that the Pentax prime lens lineup isn't crazy fast when looked at by an uninformed 35mm shooter, the Pentax zooms didn't appear particularly appealing on the surface either.

Since it seems that you can't directly compare FF and MFD numbers with regard to aperture, DOF etc., one way to compare is looking at photos taken with various lenses and settings on a 645D. Since I don't really feel like renting a 645D setup at this point in time, I think it's fair to ask the question from those with experience. It's not carrot dangling, just a question ...on a forum.

Having said all that, the primary use is for portraits and weddings. I have a contract for indoor soccer for another 3 months, but sadly it's not being renewed. For personal enjoyment, I do landscape and street photography. The reason for considering the 645Z is the increased resolution (move from 12 and 16Mp), and more critical lens performance.

I have the following lenses: 24/1.4, 50/1.4, 85/1.4, 105/2.8 and 200/2. In reality I could happily live with just the 24, 85 and 200. When I review my files, all of these lenses are somewhat disappointing in some way with the exception of the 200/2. Funnily enough, a while ago I was ok with their performance but I guess over time my taste/skill/whatever evolved and that's no longer the case. I also had a play with a colleague's IQ160 files in Capture One a while ago. This probably didn't help in terms of awareness of what's possible. Call it file envy if I'm honest.

To finally make my point: if there are 3 lenses in the Pentax lineup that deliver better detail and colours with similar out of focus rendering characteristics, I'd be happy to sell the D4 and the primes and get a 645Z with 3 primes. This would allow me to keep the D700 and get a 24-70/2.8 as a secondary wedding setup. I hope that makes things a bit easier to respond to.

[Ryan Tischer]

I think this depends on your subjects and shooting style more than anything else. I shoot landscapes and almost never any portraits and rarely wildlife... I do huge prints and don't usually need fast lenses, so the MF makes great sense for me.


If you're shooting a lot of sports, wildlife, or low light then I'd stick with the Nikon since you're so invested already. The 645Z will have much better ISO capabilities, so you can probably just crank that up to make up for some of the 'slowness' of the MF lenses. DOF will probably be similar due to the larger sensor size.


You aren't going to be able to cover an equivalent of 14mm-200mm in three zooms, I can tell you that now! You'll need the 25mm (or wait for the new rumored zoom), 33-55mm, 55-110mm and/or 45-85mm and 80-160mm, and 150-300mm, which would be a near back breaking load of lenses! The 35mm, 45-85mm, 80-160mm can all be had for quite reasonable prices, but the 25mm is at best $3500 used +...I'd guess 6K plus for the new wide angle zoom if and when that is released.

---------- Post added 04-22-14 at 11:10 AM ----------

That being said I have the 25, 35, 45-85, 75, 120, 80-160, 200, 300 and they are ALL VERY SHARP, so much that compared to my old canon L series glass the Pentax blows them out of the water. I also love using the manual focus 35mm...so easy and bright to focus and simple!

[KGH]

Having said all that, the primary use is for portraits and weddings

Funkysmurf- I recently bought a second hand 645D for portraits and weddings. Haven't had any in the three weeks or so since getting it, but am very enamoured with it. I also bought the only lens, a 75 FA. Strangely I haven't felt the urgency to buy another lens yet. I mean I know I will need more for weddings and other uses, but am just waiting until I find a great deal. The 75 is just a wonderful all around lens. I use it for close-ups and groups, even of covered bridges and candids. And Adam, I hand hold mine quite a bit. I find it very sharp this way, my wife not so much...I do bring along the tripod more often though. If I had to get just two more lenses, it would have to be the FA 33-55 and the FA 150 2.8. The zoom would be very useful in the pre ceremony and reception times, as well as a good wide angle for groups, and the 150 should give me the wonderful shallow DOF on full length brides that the 75 gives me on close ups. Of course there are others like the 120 macro because I find macro shots interesting, but not essential to business. Remember, with 40 or 50 mp you can shoot wide and crop in on events like weddings and still have plenty of detail. you don't have to have every single focal length in your case.