I haven't found that to be a real problem. I regularly enlarge 4x5 with a 135 mm EL-Nikkor and have no issues with light fall off at the edges.
Originally Posted by Mick Fagan
Frank, yes normally it isn't a problem, but if you shoot something on 4x5 with a 90mm lens then depending on the coverage of that lens there is the possibility of light fall-off around the edges. Maybe about ¼ of a stop fall-off.
If you then enlarge with a slightly wide lens that has something like 1/8 of a stop fall-off, then you are looking at a possible 3/8 of a stop fall-off at the extremes.
Quite a lot of people use oldish wide angle lenses, my own 90mm lens is a case in point. It is a Schneider 6.8 90mm Angulon, it has light fall-off measured on the baseboard of a ¼ stop, at the full frame corner edges.
Using a friend's 135mm enlarging lens we measured fall-off at the baseboard at 1/8 of a stop at the negative edge.
Using my Componon S 150 enlarging lens we measured light fall-off of 1/16 of a stop at the negative edge.
Not much, but there and measurable and actually possible to see with the eye, on a straight print.
If you need to enlarge full frame then it could become a bit of an issue, or at the least, you should be aware of these things.
Comparing the falloff of the Componon-S 135 and 150, they are nearly identical when stopped down. The 150 is slightly better when wide open. BTW 151mm image circle for both comparisons.
Last edited by ic-racer; 10-05-2008 at 09:41 PM. Click to view previous post history.
IR, I take your point, but I measure on the base board, I take nothing for granted.
It is there that I firstly see a slight difference, then I measure that difference. It isn't a problem but when a lens is put onto an enlarger there are other variables, especially evenness of light distribution.
By it's nature any 4x5 equipment will be built to a professional level and should perform equally, but in reality there are always subtle differences.
If you do know about any possible equipment deficiencies or differences beforehand, then you can take them into account when evaluating your possibilities.
I sometimes wonder which "beautifully made and cleverly designed British enlarger with a formidable professional-use reputation that I refuse to buy or use...because it has a glassless carrier" is referred to by Barry Thornton in "Edge of Darkness"
It does sound very suspiciously like a DeVere; there can't be too many Pommy enlargers that match that carefully lawyer dodging description .
That said, I've not had focus problems ever with my 504, and would never change it.
Regards - Ross
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I actually did not see your post but, I don't disagree with your results on the 135 you tested. Always best to test!
Originally Posted by Mick Fagan
I have an LPL and am extremely pleased with it. The spring counter-balance is perfect, so you can lift the entire head up & down with your little finger. There is a remote-focusing want that is simple and works well. I had a Zone VI and a Beseler before, and the LPL is much better. It's a well thought-out design.
Originally Posted by ITD
Another vote for the De Vere 504 from me. I have a 504 and 203 each with the Ilford 500H MG heads and they are the best I've used for mono work. If you hunt about a good 504 should come your way for £300 to £500 ish on Ebay - but you will have to travel to collect it. If you end up with a 504 with a MG head version your RH Designs f-stop timer will not work the MG Head as the MG Head uses its own dedicated timer and probe. However, RH Designs do a special version of their superb Analyser for the Ilford 500H MG Head which works it beautifully. Talk to Richard at RH Designs for more information.
All the best,
The aim of art is to represent not the outward appearance of things, but their inward significance.
Yes, I’m quite pleased with my Jobo/LPL 7450. Apart from the features Charlie mention I particularly like the VCCE module that, almost, keeps the exposure constant when changing filter grades. To me it also appears that LPL’s claim that their diffusion boxes are capable of higher contrast than ordinary diffusion enlargers is true. However, this assertion is only based on limited experience with other diffusion enlargers.
Originally Posted by voceumana
What I don’t like is that it’s hard to align the LPL enlargers since it has to be done with shims.
That is also my experience when enlarging negatives, exposed with a 90mm f4.5 Grandagon, with a 120mm Rodenstock Rodagon WA.
Originally Posted by fschifano
But then again, I have not measured the light falloff.