Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-15-2012, 08:28 AM   #76
Pentaxian
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
/talkingoutofmyassmode

maybe that knob moves a lens element back and forth o_o

02-15-2012, 08:54 AM   #77
Pentaxian
panoguy's Avatar

Join Date: Sep 2007
Location: Washington, D.C.
Photos: Gallery | Albums
Posts: 3,290
QuoteOriginally posted by Caat Quote
I can understand pre-production models getting a bit worn as they must get handled a lot as part of the design process. But the nature and positon of that mark just seems a little hard to explain any other way. Of course the fact that it's hard to explain doesn't mean the lens is telescoping at all.
Well, you've stated the best explanation right there - it's a pre-production model and has probably been subjected to some abuse. It's entirely possible that this "working mockup" (with glass, mount, electronics, etc.) is/was telescoping and retractable, but that the decision to make all future production models the same way has either not been made or is highly in doubt... so no mention of this capability!

Would it be great to have a collapsible 560mm long-lens? Oh, yes!
Would it still be great if the lens could be thrown out of optical alignment due to regular use? Uh, no...

Given that so much of this lens design (apparently) comes from existing scopes, there are questions galore, both from the curious consumer, and I'm sure for the team finalizing and testing the design! Gotta be patient...
02-15-2012, 09:07 AM   #78
Pentaxian
bobmaxja's Avatar

Join Date: Mar 2010
Location: Laval, Quebec Canada
Posts: 1,736
It's a prototype, peoples should just take the minimum prerelease spec
02-15-2012, 11:50 AM   #79
Veteran Member




Join Date: Sep 2006
Location: Southern Calif
Posts: 564
Slapped together quick

parts off the bench to show something for CP+ would be my take.


Way too soon to make any guesses on what's what at this time.

02-15-2012, 12:08 PM   #80
D0n
Banned




Join Date: Jan 2012
Posts: 530
I do not see why the optical formula would fall out of alignment on a collapsable lens... assuming the lock collar only locks the lens when collapsed, but when extended, the barrels snap (ie bayonet locks like on the petal lenshoods) or screws together by twisting, then the lens could in fact be WR and collapsable with no issues on lens alignment... so from a closed, collapsed position, you'd unlock it by twisting the knob on the body... pull it open, then twist to secure it in place while open, and shoot... no problem. The locking knob woul only come into use when carrying or storing the lens in the collapsed position.
02-15-2012, 05:30 PM   #81
Pentaxian
panoguy's Avatar

Join Date: Sep 2007
Location: Washington, D.C.
Photos: Gallery | Albums
Posts: 3,290
QuoteOriginally posted by D0n Quote
I do not see why the optical formula would fall out of alignment on a collapsable lens...
In case you misunderstood, I didn't say that simply making a collapsible lens would mean the optics would fall out of alignment, but rather that a collapsible lens (like any zoom lens that extends an retracts) requires more engineering and thought to insure that it is rugged and will remain in alignment (as opposed to a simple long lens telescope). The bigger the lens, the more it could be a factor due to weight of elements and housing, etc.

My Sigma 150-500 extends and collapses without any problems, but then it was designed to do this from the beginning. A telescope might not have been... (also, my Sigma is a $1k zoom lens, not a $3k-or-whatever prime)

Last edited by panoguy; 02-15-2012 at 06:12 PM.
02-15-2012, 07:07 PM - 1 Like   #82
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,149
From the images the lens is definitely collapsable unless someone have fiddled in Photoshop for fun(?).
The fact that this type of telescope design might leave softer edges may be of no consequence on a APS camera. The A* 600/5.6 weights 3,2kg; this one should be lighter. Ie it is handholdable! If the design also make it cheaper than a traditional super telephoto, then Pentax have a winner here. Seems they once again made a product that emphasizes the pros with APS. APS is at least my first choice for long telephoto work.

It is also nice that they have choosen to depart from the awful and non-durable silver finish of the FA* lenses. This has the white finish of the A* series; those were beautiful. They should make the tripod collar white on the finished product; it look too much add-on aftermarket in black...

Last edited by Pål Jensen; 02-15-2012 at 07:13 PM.
02-16-2012, 12:39 AM   #83
Veteran Member
starbase218's Avatar

Join Date: Sep 2009
Location: Planet Earth, Sol system, Milky Way galaxy, Universe
Posts: 1,110
QuoteOriginally posted by Pål Jensen Quote
From the images the lens is definitely collapsable unless someone have fiddled in Photoshop for fun(?).
The fact that this type of telescope design might leave softer edges may be of no consequence on a APS camera. The A* 600/5.6 weights 3,2kg; this one should be lighter. Ie it is handholdable!
Well, maybe if you tie a few helium-filled balloons to the barrel or hood.

02-16-2012, 04:17 AM   #84
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,149
QuoteOriginally posted by starbase218 Quote
Well, maybe if you tie a few helium-filled balloons to the barrel or hood.
Huh?? I used the A* 300/2.8 at 3kg it was very handholdable indeed. I've even handheld the 7kg 600/4 but it is not recommended and you really need SR!
02-16-2012, 04:28 AM   #85
Pentaxian
gazonk's Avatar

Join Date: Feb 2009
Location: Oslo area, Norway
Photos: Gallery | Albums
Posts: 3,512
QuoteOriginally posted by Pål Jensen Quote
Huh?? I used the A* 300/2.8 at 3kg it was very handholdable indeed. I've even handheld the 7kg 600/4 but it is not recommended and you really need SR!
Some people even shoot with the 16kg Sigzilla monster handheld :-)
02-16-2012, 05:41 AM   #86
Veteran Member
Asahiflex's Avatar

Join Date: Jan 2008
Location: Netherlands
Photos: Gallery
Posts: 2,754
QuoteOriginally posted by Pål Jensen Quote
Huh?? I used the A* 300/2.8 at 3kg it was very handholdable indeed. I've even handheld the 7kg 600/4 but it is not recommended and you really need SR!
I have tried the A* 300/2.8 (albeit for a very short time) and I did not find it very comfortable to use. But it's a great lens indeed...
02-16-2012, 06:06 AM   #87
Veteran Member
starbase218's Avatar

Join Date: Sep 2009
Location: Planet Earth, Sol system, Milky Way galaxy, Universe
Posts: 1,110
QuoteOriginally posted by Pål Jensen Quote
Huh?? I used the A* 300/2.8 at 3kg it was very handholdable indeed. I've even handheld the 7kg 600/4 but it is not recommended and you really need SR!
This isn't just about weight. The DA 560/5.6 is a good bit longer (in terms of size) than the A* 300/2.8, so I assume the center of gravity is much farther away from the camera. Anyway, I don't see me using it without some kind of support.
02-16-2012, 10:11 AM   #88
Pentaxian
rvannatta's Avatar

Join Date: Aug 2007
Location: Apiary, Oregon
Photos: Gallery
Posts: 1,176
QuoteOriginally posted by Asahiflex Quote
Sorry, I was wrong indeed (I don't see the A*'s that often). But the knob was never part of the lens barrel but always part of the hood.

IMHO the ribbed pattern around the ring on which the first knob sits makes clear that something can be done with that part. And I think it's telescoping indeed.
Yes--I have 3 long A*'s all have thumb screw locking telescoping hoods., but alas, I think that thumb screw on the 560 is the hood lock
as well----andn is part of the hood. I think the hood is of reduced diameter on the back and reaches all the way back to the thumb screw
and indeed everything you see there does slide back as suggested--- but only the hood moves, not the front element.

the annoying thing about the locking screws on the A* series is that the locking screw sticks out past the max diameter of the lens (and hood)
making it the first thing to get hit and broken if you bump something. I very much like the concept of sliding hoods. I am aware of few
people that like the screw on hood of the FA*3002.8 better than the sliding hood of the A* 300/2.8. the usefulness of these contrast greatly
to those often not well liked telescoping hoods on smaller lenses in the Pentax A family that seems to sort of flop around at will because they
didn't have locking screws. If there is indeed a cup shaped hood with the locking screw as pictured (onthe smaller diameter barrel), I will consider that a major improvement over all of the other hood approches that Penax has used.
02-16-2012, 10:27 AM   #89
Pentaxian
rvannatta's Avatar

Join Date: Aug 2007
Location: Apiary, Oregon
Photos: Gallery
Posts: 1,176
QuoteOriginally posted by Pål Jensen Quote
From the images the lens is definitely collapsable unless someone have fiddled in Photoshop for fun(?).
The fact that this type of telescope design might leave softer edges may be of no consequence on a APS camera. The A* 600/5.6 weights 3,2kg; this one should be lighter. Ie it is handholdable! If the design also make it cheaper than a traditional super telephoto, then Pentax have a winner here. Seems they once again made a product that emphasizes the pros with APS. APS is at least my first choice for long telephoto work.

It is also nice that they have choosen to depart from the awful and non-durable silver finish of the FA* lenses. This has the white finish of the A* series; those were beautiful. They should make the tripod collar white on the finished product; it look too much add-on aftermarket in black...
I personally much prefer to use the 300/f2.8 class lens with a monopod (either the A* or FA*--I have both at the moment) though I have hand held them with success, but I can't make a case for using either the A*400/f2.8 for the A* 600/5.6 with less than a full tripod. I just hope that
the tripod mount is somrwhere near the center of balance on the 560. I regard the fact that the tripod mount is about 6 inches off of the
balance center on the A*600/f5.6 as design malpractice.
02-17-2012, 02:35 AM   #90
Senior Member




Join Date: Jun 2008
Location: Paris
Posts: 175
Do we know for sure that it won't have strap lugs? If so, what a bummer! I'm using my Sigma AF 300/2.8 and 2x TC handheld (I didn't find it too practical/comfortable mounted on a monopod), and since it doesn't have strap lugs either, I have to keep the tripod foot in place to be able to carry the lens and body with a Blackrapid-type shoulder strap (it screws into the foot).
I'd much prefer to tie both ends of a classic shoulder/neck strap to lugs, for instance using one of the lens' at one end and one of the body's at the other (it seems to me it would be that much more justified if the lens is very long - less rocking that way).

PS: incidentally, even when mounted on a monopod, I use a longish quickplate with holes at both ends, to which I tie a neckstrap, in case the monopod slips from my hands.
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!
cp, lens, pentax news, pentax rumors, wr
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pentax 560mm ? ElJamoquio Pentax News and Rumors 928 09-30-2012 08:07 AM
Front/Back Focusing Mapleleaf-Mick Pentax K-5 2 01-05-2012 08:04 PM
Front to Back Sharpness: Distance setting on front of lens yoon395 Troubleshooting and Beginner Help 18 09-08-2010 04:33 PM
Need help regarding back-front focus test. marography Pentax DSLR Discussion 5 06-14-2010 03:34 AM
Front/back focus adjustment on K7 braver Pentax DSLR Discussion 3 03-08-2010 08:35 PM



All times are GMT -7. The time now is 07:23 AM. | 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