Long exposure time for Leitz V35 Focomat

[raytoei@gmail.com]

Hi,

i finally got my dark room set up (in 2015 yay!).

i am using a leitz focomat v35 enlarger with replacement philips 13139 bulbs.

having printed around 15 8x10 prints, i find that my average exposure is around
45sec to 1m and if variable-contrast is used, it goes up to 2 - 3mins (!).

Is there something wrong with such long exposures ?
(or is there any upsides to long exposures ?)

i use f5.6 aperture on the 40mm focotar and I am wondering if f2.8 would be too "soft".

the reasons i understand are:
* Diffuser head taking longer time
* Incorrect bulb
* Filters (i am using the color hear)
* apertures

thanks !

raytoei

 

[presspass]

Seems like an excessively long time. I've been using a V35 since the late 80s, always with Variable Contrast RC paper - mostly Ilford Warmtone. I have never used the color head; I use a variable contrast head with the Splittone system and get exposures ranging from 16 seconds to 35 seconds, depending on the negative, for 8X10 prints. These are all at f 5.6. Does your enlarger have the regular module - no filters at all? If so, give that a try just to see if the times drop dramatically. BTW, Leitz also made a VC module for this enlarger. Hope this helps.

 

[sevo]

This is way too long - exposure times, even for a large format print, are assumed to be below 30s. All filters set to zero? Voltage supply set to the right voltage (assuming you have a 220/110V switchable one), and you are not running a 220V fixed supply in a 110V country either?

 

[raytoei@gmail.com]

Hi,

Just received 13139 original bulbs from ebay, will be installing it to see any improvement in exposure times.

Thanks again.

 

[Ronald M]

If it came with the old bulb, you will need the new holder.

Also the bight box was fitted with double condensers to spread light better. There will be a pin mark in the diffuser surface corner indicating double.

 

[raytoei@gmail.com]

thanks for the all reply. after installing a rare original philips 13139 bulb, my dev has gone down to a more manageable 30-60seconds, with contrast filter (color head) turned on and f4 aperture. Still not as short as my russian upa725 with a condenser head (15 seconds @f5.6 with same contrast grade and same negative), but i am not complaining.

 

[Fotohuis]

Probably alignment, old bulb and old Styrofor diffuserbox which you can replace by a new one (Kienzle in Germany).

Philips 13139 75W is not in production anymore for several years. But in time you can replace it by a LED cold light source (Heiland Germany):
http://shop.fotohuisrovo.nl/product_info.php?cPath=44&products_id=506&language=en

With the Focotar F/5,6 aperture and 8x10"/20x25cm prints it should be 20-30s max. in exposing time.

 

[Fotohuis]

At least when using Bromide photo papers. When using Chlorobromide they are approx. 3 times less in sensitivity.