Delta 100 and the lens-less camera

This is not the first time I have mentioned sharpness when it comes to pinhole photography. I know! not something you associate with the dream like quality of the images it produces. It is part of the reason that draws me to using a pinhole camera but it does not stop me speculating whether a T grain film would enhance the detail and therefore increase the sharpness.

I have already informally checked out the idea that Rodinal/RO9 could go some way to increasing sharpness which was done some time ago. (if your interested in that article I'll post a link at the end) The results did confirm that there was something in my observations. I will reiterate that the sharpness increase will not rival that of a lensed camera.

Delta 100 @100iso developed in RO9

 I did find that PMK Pyro developed negatives, when printed looked softer to the pictures produced from negatives processed in Rodinal/RO9 in a very subtle way. This then lead me on to thinking would T grain film with it's enhanced sharpness show a difference when used with a pinhole camera. Better still would it get a double boost when combined with Rodinal/RO9 developer?

 

Contact print on Fotospeed RCVC

So is there a difference? Yes a  noticeable one it has surprised me the level of increase. I'm not sure how much is down to the film alone because the film was developed in Rodinal/RO9. I suspect that most of it is from the films T grain and the developer has just enhanced the equation. 

What do I mean by an increase of sharpness - it shows it's self with a better defining of the details across all areas but still maintains that softness you expect from lens-less images. 

All the above were printed on Fotospeed RCVC paper developed in Ilford multigrade 

Link to older post on sharpness

Enlarging lens revisited

Recently black and white photography magazine has been celebrating it's two hundredth edition which gave me impetus to rediscover what was in some of those back issues. While thumbing through one issue, an article about enlarging lenses caught my eye, reminding me that I have been meaning to revisit the subject.

I have written a couple of small articles: Enlarging lens and which aperture  I re-read both before writing this one so as not to repeat myself. But that is not going to be easy as the main issue with enlarging lenses is quality. The rule of thumb is to choose a lens of six or more elements. The Componon-s and Rodagon are two modern designs that work very well - they are two quality makes of the few still available new.

Looking down a focus finder at F5.6- F8

In the 1970s Nikon special optics division set about producing a darkroom lens second to none ( Apo-EL-Nikkors ). It was done in a one off batch, releasing a number to the market over a ten year period until they were all gone. It has been said that at the end of this period they did consider doing another run but stopped doing so because they would have had to sell the lenses for £12,000 each. I do not know if this figure is true or not. If it is, it will have made the original runs price in the thousands and therefore out of the reach for most of us.

The enlarging lens has one job to do and that is to project the the image from the negative to the paper perfectly. The one hindrance to good enlargement method and creativity is poorly maintained or ignorantly used enlarging lens practice. It is not good enough to think if you close the lens right down, like you would a camera lens, that you will increase the sharpness of the image. The rule again is to close the lens down by two F numbers. In a lot of cases this produces the optimum sharpness. One stop more may result in a softening of the grain structure. This does not mean that you will notice a softening of sharpness with the mark one eye ball as the image is projected onto the paper. Like a lot of things in photography the kit is made to a greater quality than can be seen in normal life.

Focus finder

Enlarging lenses should not be treated as second class citizens as they are several time better in quality than the camera mounted counterparts. They do their best work in a very narrow range of magnifications. For 35mm negatives the lens is optimized to 10x its size which equates to an enlargement of 10x8. As you go up the format scale this decreases 6x6cm lenses 6x and 5x4in 4x magnification. As you push past the optimal point it increases the possibility's of grainy photographs. This is not to say you should not push beyond this point as experience has shown. You can negate this by using ultrafine film developers.

Grain at f11

How do you see which is the best apertures to use? You need to complement your lens with a good focus finder. This magnifies the grain of the negative so you can see it. The best way to use the finder is to have the enlarging lens fully open. Place the finder in the middle of the baseboard. While looking down it at the grain, adjusting the bellows until it separates into little defined specks. This will mean that you now have fine focus.

While still looking down the finder shut the lens down a stop at a time. There will be a point where the look of the grain go's slightly soft and becomes softer the more you close it down. You should remember that you are still at optimum focus. To test this you can try to adjust the sharpness in most cases it will get worse and become to difficult to regain any sharpness until you go back to the optimum aperture.

Grain at F16 looking down the focus finder.

What has been described above is my experience with one of my 35mm enlarging lens. I will point out that it is not a well known make. It is one I use often. The softening of the grain in the focus finder is not transferred to a softer looking image on the baseboard that can be detected with the naked eye but you will start to question whether it is affecting the quality of your images. The only way you will know is to borrow or buy a better quality lens and do a comparison.

When considering buying a lens you should spend as much as possible to ensure that you get a good to very good lens. Knowledge that the lens is not what you expected will impact on your photography subconsciously.  

Schaimpflug's rule.

This is the rule on tilting the easel and carries on from my last post.  The most accurate way of correcting distortion is to use Scheimpflug's principle: This states that you should tilt the negative as well as the baseboard and that they need to be canted over in opposite directions to each other. Additionally the incline should be such that the plane of the negative and the plane of the baseboard should meet in the plane of the aperture to give maximum sharpness over the whole image. 

You will find that the more expensive enlargers allow the plane of the negative to be tilted, add a tilting easel to the mix and the results produced can be remarkable.

Related posts:

Tilting the easel.

Enlarging len which aperture?

The quality of your enlarging lens will lead to better and sharper results at greater magnification. The aperture ( low number = large opening, high number = small opening) you set not only affects the amount of light it lets through but the depth of field as well. A good average aperture is F/5.6 in most cases. If the exposure times are to short a larger F number is needed, this will give you a chance to hold back shadow areas that may become to dark to show any detail. But don't get carried away and close down the lens by too  many F numbers as this may over heat the negative causing it to buckle, making the picture loose sharpness.