[Bob 256]

Ditto on what Thagomizer suggested. Using a flash and a good diffusing medium behind the slide (ground or opal glass) would provide a consistent source and also eliminate any worries about movement during the exposure, leaving only the aperture to worry about. You can then adjust exposure using the flash (if it has variable output), the distance from the flash to the diffusing medium, ND gels in that space, or a combination thereof. Place the diffusing medium a small distance behind the slide so any dust specks will be well out of focus. Some flashes provide a modeling light which is needed for your initial viewfinder focus adjustment.

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Last edited by Bob 256; 01-03-2019 at 09:45 AM.

[jjbuzard]

Yes used the 2 second lock up and turned off and on Shake Reduction, sill same problem

[jjbuzard]

Wow, didn't expect all this response, I am shooting with Pentax SMC 50mm f 4 wide open at f 16, will try closing down to f 8 to f 11., speed is around 10th to 20 sec, shoot adjust and shoot, using Copy stand photo bulb 250 watt 4800K on my copy stand, about 4 feet away constant source of light. yes the slides have some bulge, but scanned them for years with no problem, I am now copying several 100 slides from Vietnam and the scanner is too slow, will read the article part 1 and 2 by Read. I am still digesting all of your suggestions and report back. Attached is a slide of me 50 some years ago on the mountain shooting with my Pentax SV with my 300mm f 6.3 and using a Clip On Light Meter. This is a slide I scanned years ago.

[AstroDave]

I am shooting with Pentax SMC 50mm f 4 wide open at f 16

Huh? Which one? Wide open = close to f 4, whereas f 16 would be stopped down most of the way (small aperture and more depth of field).

[clickclick]

I've not done any slide reproduction work myself, but my assumption would have been to use a lens with the flattest possible field of focus...

I'm going to give a tentative yes. I started venturing into this awhile back, and in the process picked up a Bowens Illumitron 3S, well, two units actually, and they come with/use enlarging lenses. As I dug around researching how to use them, enlarging lenses were the choice for the flat field, since you were copying something flat. Of course, this assumes your slides are flat.

[Wheatfield]

Sorry to take things slightly off topic here, but I find this interesting. I can understand there may be distortion in slides, but I'd have thought a flat field lens was still better - just stopped down to allow increased depth of field (and hence allowing for the distortion). Am I wrong?

This is a genuine rather than rhetorical question. I've not done any slide reproduction work myself, but my assumption would have been to use a lens with the flattest possible field of focus...

If you look at a mounted slide, there is almost always fairly significant curl towards the emulsion side. The trick is to face emulsion to emulsion, or in this case to the sensor, and use a lens with some field curvature. The curvature will never match perfectly, but it will be an improvement over a flat field lens. If you have your slides in glass mounts, or if the slides have little curl, then a flat field lens is called for.
I find stopping down to at least F/8 gives best results.
Some lenses just give really bad results when used as close focus lenses. I’m not sure if this is part of the problem the OP is having.
I’ve been digitizing some of my old negs and slides of late. I’ve been using enlarger lenses for the optic on the bellows. They are flat field, so have to be stopped down a lot if the slides are curved, but I have better enlarger lenses than camera lenses in the required focal lengths that will fit the equipment. Also the neg holder seems to keep things flatter than slide mounts flatten transparency film.

[jjbuzard]

Are you using the 2 second lockup or turning off Shake-Reduction?

To Not a Number...Yes I am doing both. I posted on page 2 as a mass answer, now I am trying to answer each individually.

---------- Post added 01-04-2019 at 07:46 AM ----------

Huh? Which one? Wide open = close to f 4, whereas f 16 would be stopped down most of the way (small aperture and more depth of field).

Sorry brain fart, focusing wide open, close down to f 16 to shoot.

---------- Post added 01-04-2019 at 07:48 AM ----------

Sorry brain fart, focusing at f 4 wide open, shooting at f 16 closed down, I am going to try closing down to f 11 to f 8 as suggested above.

[clickclick]

shooting at f 16 closed down, I am going to try closing down to f 11 to f 8 as suggested above.

Don't foget that many lenses start running into diffraction issues stopped down into this range. I'd do a series of test shots stopping down a click each time, and then see which f stop gives you the sweet spot. I'd expect it's going to be more like f 5.6. Of course, as pointed out with curving of the slide, you are going to have to balance depth of field too.

Also, if you shop around, enlarging lenses are relatively cheap if you want to play with them. I picked up a nice El Nikkor 50mm for about 10 bucks on eBay. I also have a Pentax bellows, and have been using a 60mm Schneider Componon enlarging lens on it. I can actually get pretty good coverage of a slide on my K3II with this lens focal length on the Pentax bellows.

[jjbuzard]

Well I tried turning the slide both ways, emulsion/ Glossy to the camera, Tried f 11, f 8, f 16, best shot I can count the eyelashes on my daughter, but only center is in focus all edges are out of focus, I guess my next best bet is to try another lens. Speed is 4 to 10 of a sec.250 watt 5000 Lumins Daylight

[clickclick]

but only center is in focus all edges are out of focus,

Even if you can't get full coverage, do you have another lens you can try? It might help to narrow down what is affecting your images this much - curving of your slide, field curvature of your lens, general quality of lens, and so on.

[jjbuzard]

I guess I could try a 35mm as opposed to going to a 55mm

[jjbuzard]

Actually all the time I have spent on this I could have scanned a couple a hundred slides!

[abruzzi]

A longer lens will not work = it will not be possible to position the lens & slide to get the latter in focus.

Actually, I use (on a A bellows) an cheap old Takumar-F 28-80 zoom. I can fill the APS-C sensor and focus with the lens at 80, but I usually shoot it back a bit ~70 to give me the space to rotate and crop later, and it works pretty well.

I don't know the features on the K10, but I'd strongly recommend not using the viewfinder, but using live mode with focus peaking if it has it. I have one of the user modes on my K-3ii set for digitizing, including turning on the 2 second delay so I get mirror lockup and my hands far from the camera so I don't create any shake. In live mode the button in the middle of the directional pad zooms in and I always zoom it in 10x, then pan around to find an area and will show the focus peaking, and adjust focus on at least each negative strip, though I will adjust mid strip if its a shot I want to be sure comes out well. I have exposure set to full manual, but I use the green button to pick the shutter speed.

Remember that the original design of the bellows involved a double cable that would stop down the lens and trigger the shutter. Since I don't use that I have the aperture locked down permanently. That is the "auto" par of auto bellows. If thats what you have, and you're not locking down the aperture before firing, you're shooting at wide open, no matter where the lens is set. If you bellows isn't an "auto bellows" its not an issue. I have the lens set to ƒ8 and have gotten sharp photos even if the shutter time is as long as 2 seconds. My light source is an open window. Its less than ideal but works.

Just an example of a scan done with this setup:

[jjbuzard]

OK after much trial and Error, I think I got it, I messed with the focus and finally when I got what looked close the camera red dot popped on and beeped, so then I started messing around with diffusing the light and finally found a happy spot with an crackle Ice panel, shooting at 2 secs and f8. the lens is the Pentax Super-Multi coated TAKUMAR . On my Pentax K10D. I reversed the slide, then took a slide mount, split it and then slid it in with the slide to hold it tighter in the holder, there is so much slop, the slide sit in there canted to one side. Here is the results over the original picture, I can recognize the driver and the old man standing behind the tractor, this slide was developed in June of 1967.

[RGlasel]

Here is the results over the original picture

A remarkable improvement, to say the least!