Filters & Light Refraction

Excellent Matt, I've 'emailed' files to be printed before and the results were pretty good but I've never really thought about converting digital images to slides - I am still quite new to it you see!

Thanks for the links, the service looks very good indeed.

Kimbo, if you're printing to anything up to 18x12" then www.proamimaging.com are superb. I've had some 16x12" prints done and they are absolutely stunning (even if I say so myself ) and extremely cost effective Small snag is you have to prepare everything - colour space, image size etc and post on CD. Benefits are: super fast turnaround (I posted on a Friday, received on a Tuesday with 1st class post), and 100% accurate results.
I'd definitely recommend them
I've also used Photobox, but have just got back better results by using a Fuji Frontier profile, rather than just sRGB (their equipment is nearly sRGB, but not quite).

Going off thread a bit...

Matt

Depending on the quality, you could get one of those slide copiers that attach to the camera, and use a DSLR to copy the slides.

I managed to find a used Polaroid Sprint Scan 120, so I can scan 35mm and 120 film. But if you only have a few slides to digitize, the copier method may be just the ticket!

I thoght the intention was to produce slides from digital images not the other way round

Kim

You're absolutely right Kim

Oops, you're right. I guess I'm just bass-ackwards today!

Well I've got lots to think about now, many thanks for all your suggestions.

Arthur, I've got one of those Ohnar zoom slide duplicator thingamajigs (T-mount PK adapter) but hardly ever used it. It works but I wasn't terribly impressed when I tried it on my SFX but I dare say that I can tweak the images from my DL and make them much more acceptable - thanks for reminding me, I'll dig it out and have a play

Hi Kimbo,
Many years ago when funds were very tight, I did try one of those slide copiers. To be honest it was a waste of time, effort and money. If you want digital copies these days you will probaly get better results from a scanner with a film scanner built in. If you want decent images, I would try and beg, steal or borrow a dedicated film scanner. If you need some duplicate slides, a bellows set up with slide copy attaxchment will give acceptable results. I can get quite good results with the 50/2.8 Macro lens, acceptable ones with a 50/1.7 and slightly less so wiyh a 50/1.4. This is what you would expect and in line with Pentax's recommendations with regards to the lenses. After all you are after good flat field performance. If you need lots of copies, the proper macro stand will give the best results and is the easiest to use.

Kim

Hi Mac,
The choice of filters is a difficult one and ultimately will depend on how you intend to use the camera and your choice of film. If you keep a lens cap on for most of the time and only remove it to take a photo, you probably don't need a filter. I tend to leave the cap off most of the time and so use a filter. A good quality filter such as the B&W MRC ones, the Hoya pro's or the Tiffen equivalent will have an effect but this will be very minor and will be less than a scratch on the lens or lots of dust. (More damage is done to lenses from over zealous cleaning than any other reason.) Another reason I use then is the protect the thread. Fortunatley I haven't scratched too many lenses but I have managed to dink the thread on a few filters! Modern polycarbonate lenses tend not to suffer from this but the older metal ones such as the Super Taks can.

The other reason your decision will be based on is the the film you use. With monochrome, I would always use a yellow or yellow/green to give a better tonal range. At the same time I would keep an orange and a red handy for an increased effect. Blue can be useful for portraits. With slide film, you may need a slight warming or cooling filter to correct the colour balance. Rember that a Skylight filter will have a slight warming effect whilst a UV is neutral. For print film, it is less important as any slight colour caste can be corrected at the printing stage. However a polarizing filter is useful for better skys and to reduce reflections off glass and water etc.

With digital, it is much easier as most corrections can be done on the PC after the picture has been taken.

Hope this helps
Kim

One filter you'll always need to have on hand is the polarizer. To re-create the effect in Photoshop is just too much work!

Besides, you can use a linear polarizer in front of a circular polarizer to make a continuolsy-variable ND filter. The problem is you now have four extra surfaces to keep clean!

Well it sounds as though we've gone full circle on the question of filters and to sum up,

1) minimise the possibility of image degradation by using good quality filters.
2) if you're not trying to correct for a particular lighting characteristic, then for maximum image quality you're probably better off not using a filter.
3) however remote the possibility of damaging the lens, it's usually cheaper to replace the filter.
4) if you don't have the filters in the first place, you'll not be able to experiment and will never know.

Ok so it's fairly easy to simulate the effects of most filters on the computer or during film / print processing but I for one enjoy setting up the camera in order for it to convey my intentions, rather than just firing away at 125/sec at f8 and adjusting everything afterward - a half-decent 'point and shoot' can do that!