Printable View
hello,
I have an old Hermagis Portrait lens, Petzval type, marked as Nš 5. I checked that it focus infinity at ~300 mm (12 inches) from image to the Waterhouse stop slot. It is quite big: 8 inches tall and lenses have a bit more than 3 inches diameter. I am planning to build up a wood camera for wet plate with it and my question is: what is the maximum plate size this lens will cover?
Thanks for any insight about it
Wagner
It would probably be a good 5x7 lens, and would also cover Wholeplate but you'd have to check how well.
Basically, this lens is the same size as the Dallmeyer 3b and the Ross cabinet no. 3 and lots of others with the same speed. With whole plate, the image at edges and corners will definitely be degraded.
Attachment 151235
Thanks for your input. Meanwhile I decided to check it out also experimentally (quick and dirty). Some adhesive tape, cooking paper, cardboard, blanket and a side table. Conclusion: at infinity the image circle for a Hermagis Nš 5, Petval design, serial number 46.559, is around 28cm. Well, whole plate is 8 x 10" or 20 x 25 cm square root of 400+625 is 32 cm, not 28. So not enough for 8 x 10". At least in landscape photos. But this is a portrait lens, so I assume it is intended to work at a greater distance from film and hence get a larger image circle than at infinity. Am I right? I could not check this possibility yet. I need to wait tomorrow when the sun will lit my curtains. Otherwise I get a image that is too dim to assess its diameter.
whole plate is not 8x10".
and yes, you're right, it will cover more at portrait distances. but it will still be too wide for a good portrait perspective on 8x10".
Yes, good point. 300 mm is like "normal" lens for 8 x 10. I will think about it. Thanks.
Would be a great portrait lens for whole plate (6.5 x 8.5") I have the Extra Rapide No. 5 which is a 25cm f3 lens. One of my favorite petzvals.
Now I see that this is a 4 year old thread. I wonder if any images were made with this lovely lens?
The answer should be there:
http://www.lereve-edition.fr/fr/doss...sier-collector
But there isn’t a direct answer there!Quote:
Originally Posted by Philippe Grunchec
The Hermagis booklet is number 5 in the series and is not quite so useful as some of the later releases.
The data for the series I no.5 is given as follows:
Focal length 310mm
Lens diameter is 81mm
“Dist. De l’obj. Au modele en pied “ 5.5 (meters?)
Format converts - carte -Album (which is very variable size, unfortunately!).
Of course, it can be be used for full plate and almost 8x10, but only when the outer regions are not required to be sharp!
No. 3 size (Hermagis had no. 1 as their biggest size) focal length 450cmm lens size 110mm covered 8x10.
I made some pics with it. Here is dry plate portrait 18x24 cm. Contact printed on Fomatone MG Classic. I trained negative retouching with this one. Didn't want over do it and maybe end up leaving a lot of spots that could have been evened. Here is a before and after.Quote:
Originally Posted by karl
Attachment 206583Attachment 206584
Very nice.
The No. 3 is beast and would likely cover 11x14. 450mm f4.5 I have a rough (incomplete) example. The no.5 is tiny in comparison. Really the No.4 (which I've never seen for sale) would be perfect of 8x10.