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Michael

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Posted on Monday, October 10, 2005 - 10:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Sorry if I'm in error, but I did not see any 'search', so...

I'd like to replace the focus screen in my istDS with one that has a split-image function, ala the P3 or the ME Super. I think the screen I want is the SB-21 which ONLY has the split-image and not the collar that comes with it ala the Super. So, if I could get a 'camera-for-parts' unit from, say, ebay, which model do I need? Some good technical info on the complete process would be helpful, too. I understand I have to be careful as the screen is very easily scratched. Anyway, thanks in advance.
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Roberto Rossi

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Posted on Tuesday, October 11, 2005 - 01:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

My understanding is that there are no different screens for the istDS;it is auto focus after all!!

The SB-21 is for the LX.You cannot fit screens from the 35mm film range into digital bodies. If you want that screen, buy a working LX plus suitable lens
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Henry

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Posted on Tuesday, October 11, 2005 - 05:21 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

My guess is you want to use old K mount lenses and you want the focus aids of an old screen. This is on the radical fringe of this forum, but we have a couple camera hackers here that might can help. I'm one! After a tinkerer has fixed a couple hundred cameras he starts thinking..."what if?"

Wouldn't it be simpler if companies just made digital backs. Of course they won't though. It'd be slitting their own economic throats. They'd not sell many new cameras!

If I was going to do this project I'd first find a junker istDS. It'll be an electronic rats nest under there and you'll need a road map.

Let me think on this further, it is interesting.

Henry
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Spy

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Posted on Wednesday, October 12, 2005 - 12:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

hi,

the af will not be a problem since af sensors are in the ground.

the problem might be the mf. manual fcusing is based on the principle that you must have the same distance lens-mirror-focusingScreen as the distace lens-film. And so if the replacement screen is thicker or thiner than the original you might be misfocusing your lens...

once upon a time I also searched for some adaptation like this but for my EOS 100 film camera. I found some interesting pages (i think in japanese but with good pictures), so try looking for "eos split circle focusing screen adapt" or something similar
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Michael

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Posted on Wednesday, October 12, 2005 - 05:45 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks so far for the input - it's appreciated. I do have some info and knowledge re this process and KNOW it can be done. The screens for the istDS (and the D) ARE replaceable - you can order at least 3 other screens for the DS right now, problem is, Pentax isn't making the mf screens and there ARE limitations to using a split-image screen on an af camera. I already know what the sacrifices are (mostly involving spot metering; focus will not be affected, ie, af) and think it is worth the try. There IS a German company that was taking screens from Pentax and resizing them, but there have been delays and then, they only sold them WITH the purchase of a DS. The company is Tekade. Anyway, there is truth to the 'too thick/too thin' as well as issue with 'darkness/lightness'. I have found out that the MX screen, if used, produces pics approx .7 EV darker. I read that the MZ-M screen is a good prospect in that the differences are smaller; I think it was +.3. So, I was wondering about the ME Super because that was the one I used to own before it glitched up. I DO use some manual focus and a Russian Fish Eye lens and THAT'S where I miss the focus precision (despite some reports that the focus wasn't really that accurate - this by other photogs - but I know when I use the manual lenses, the focus is too wide a range for my eyes that I KNOW I'm guesstimating. That's what getting older can do to eyes, ya know?? Heh. So, I haven't read/heard about the screen in the ME Super and since this is one that routinely appears in 'cam-for-parts' ebay auctions, I figured it might be a candidate. I have since learned that getting the screen OUT of a Super isn't easy - it involves re/de-soldering and other less than pleasant operations. I was hoping SOMEONE on this forum had done such before and was willing to help me attempt this experiment. As I said before, I know care has to be used and that it IS possible for the screen to be replaced, so, I'm willing to put in the time, but only if I think there is some reasonable success. I CAN get a screen and might still do this, but the cost is high enough that I think I'd like to try myself, first. Trying to keep the $$ ready for lenses, not screens, ya know? Anyhow, if anyone can add to this discussion, I'd appreciate it. Right now, I plan on trying to get what I need from an old P3 which might come my way. Still waiting, but the price is right. All I have to do is supply some time and effort.

Michael
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Glenn Middleton

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Posted on Thursday, October 13, 2005 - 11:01 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

What about using a Pentax viewfinder magnifier? The Canon A series one will fit the EOS range.I think Pentax made one for their film slr cameras.I am sure you could modify the fitting bracket,if required.

I routinely use one on my A1s - yes age does do the old eyes in!

For interest are the istDS / D screens really user replaceable, or is it a factory return job?
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Michael

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Posted on Thursday, October 13, 2005 - 06:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I hadn't thought of a viewfinder magnifier. I guess I got so used to just 'aligning vertical lines' that I got dependent on that. I can check it out - thanks. And yes, the screens ARE replaceable, but you have to be very careful and usually, when you buy a new screen, it comes with a specialized 'tool' (a type of tweezer) for gripping the screen where you're supposed to. Thanks for the tip.
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Donnie Strickland

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Posted on Friday, October 14, 2005 - 03:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I like using my old lenses with my dslr so I contacted Pentax about a split-image screen and this is the reply:

Donnie,

Thank you for contacting Pentax Imaging Company.

Pentax does not produce a split-image focusing screen for the *ist D or *ist DS models. This is because AF functions and multi-zone metering can be "confused" by the use of such a screen.

Pentax produces the following focusing screens for the *ist D and *ist DS models:

#38571 LF-60 AF Frame Matte $62.00 (Pentax List Price)

#38572 LL-60 AF Divided Matte $62.00 (Pentax List Price)

#38573 LI-60 AF Scale Matte $62.00 (Pentax List Price)

(Pentax List Price does not necessarily reflect actual dealer price).

Although Pentax is not a dealer or a store, as a courtesy to you, (for US residents) accessories may be purchased directly from Pentax Imaging Company, at full list price, plus shipping and handling, and tax (if applicable). Please have your VISA, MC, or DISCOVER card ready. However, all sales are final and there are no refunds or exchanges, if not satisfied.

For a current listing of Pentax Dealers in your area, we suggest you check out the Dealer Inquiry Map on the Pentax Home Page. Please point your browser to www.pentaxusa.com Click on "Dealers" and then simply click on the two letter state code for dealers in the state you wish to check, and they will load in a few seconds. You may also research dealers by entering your ZIP code and radius of search. However, because of the vast size of our dealer network, information regarding dealer inventories is not available at Pentax Imaging Company.

You may also consider purchasing from a mail order dealer, as listed in photo magazines, or contact Berger Brothers at: 800-262-4160.

We hope this helps.

If you have any further questions, please feel free to contact our Customer Service Department at (800) 877-0155.

Thanks again,

Joe Virgil

Pentax Imaging Company


I ended up buying the divided matte screen for my *istDS from Pentax online (it divides the screen a la "Rule of Thirds"). I find it helps my composition. No help manual focusing, though.

As stated above, the screen is easily replaceable. Pentax even encloses the little pair of plastic tweezers needed.
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Henry

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Posted on Friday, October 14, 2005 - 09:30 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have been studying this too. Polarization is the key.

Not sure you can get there from here and keep the metering functional.

Henry
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Michael

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Posted on Saturday, October 15, 2005 - 09:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I already have someone else's testing re the metering; only spot metering is affected, matrix is just fine, so, that issue is moot. The idea of a 'darker/lighter' screen is valid, though. As I said, seems the MZ-M is one that can be used. Unfortunately, nothing on ebay as of yet. Seems the ME Super is all the rage, though - that is why I was wondering if anyone here had attempted this to give me an idea how well, if at all, this particular screen might work. I can get the SB-21 screen, which is a split-image only screen that can be used on the LX, for about $39 from BH. That may be the way I end up going as I'll at least not have to worry about screen removal (from a used one) but still would have to 'adapt' re re-sizing, the screen. As noted before, this is an experiment in trying to get inexpensive screens and with modification, use them in the DS. The new screens mentioned in the email from Pentax are about $60. While the cameras ARE AF, the need for more critical focus is increased when you're trying to use some of the manual macro lenses Pentax (and Tamron) make. Most of those that are doing macro and having great success, are advising manual focus, so, the AF is not as important and since I can live without the spot metering and use center-weighted, I'm willing to continue the try.

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