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Phase One P25 or P25+

emendoz1

New member
I don't know if this has been covered here before. My apologies if I'm late to the party but I'm trying to find out if there are real working diferences between the Phase One P25 and the P25+ backs. I am looking for an addition to my Hasselblad H2 film camera that can cover basically or almost the entire field of view and the P25 is the least expensive back I could find to do this. I'm not really interested in lots of megapixel as I am mostly going to shoot film but a decent size digital image would be a good addition not to mention safety net in case my film never makes it back from the lab.

Again, if this has been covered before please forgive my post.

Thanks

Ed
 

lance_schad

Workshop Member
Here are some of the differences between the P25 and P25+ are:

Exposure:
P25 30sec
P25+ up to 1 hour (as per specs)
ISO:
P25 full res iso 50-400 @ 800 half res
P35+ iso 50-800
Screen:
P25 - Reflective LCD (better outdoors in daylight)
P25+ Backlight LCD ( better quality imo)
Live Preview Tethered
P25 - No
P25+ Yes
Dynamic Range
P25+ had improvements-Dynamic+
Color
P25+ had improvements - Opticolor+

This is all I came up with off the top of my head.

Lance (email me)
 

FredBGG

Not Available
Here are some of the differences between the P25 and P25+ are:

Exposure:
P25 30sec
P25+ up to 1 hour (as per specs)
ISO:
P25 full res iso 50-400 @ 800 half res
P35+ iso 50-800
Screen:
P25 - Reflective LCD (better outdoors in daylight)
P25+ Backlight LCD ( better quality imo)
Live Preview Tethered
P25 - No
P25+ Yes
Dynamic Range
P25+ had improvements-Dynamic+
Color
P25+ had improvements - Opticolor+

This is all I came up with off the top of my head.

Lance (email me)
While I really like the p25+ the live view is a joke....
Looks like crap and you'll most likely have a seizure trying to use it.

However the other improvements are quite significant.
 

torger

Active member
I've noted that there is like a zillion second hand P25 backs out there (at attractive prices), but quite few P25+. Is it because they are still used, or were very few of those sold?

I've started to realize that the long exposure capability is a rather attractive feature...

As a bystander I get the feeling that Phase One marketing has a very strong reason to exaggerate the improvements from P25 to P25+ to make people upgrade. I wonder what the difference in practice of opticolor and dynamic range is... I'd guess that P25 is pretty ok already and that the difference is very small. I haven't been able to find a P25 vs P25+ raw comparison though.

The long exposure thing and better screen seems to me be the real improvements, that actually can make a difference in practical photography.

I'd love to get a P25+ but there's like ten P25 sold for every P25+, so they are pretty hard to come by. So I'm currently struggling with the question "is P25 good enough?".
 
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gazwas

Active member
I've shot with the non plus versions of the P20, P30 and P25 and never found the output quality of the file was anything short of staggering.

The plus back screen is a an improvement but its still not that great. As for all the other stuff, unless you need exposures more than 30 seconds (15-20 max usually for me) the none plus backs are a great buy.
 

torger

Active member
I've shot with the non plus versions of the P20, P30 and P25 and never found the output quality of the file was anything short of staggering.

The plus back screen is a an improvement but its still not that great. As for all the other stuff, unless you need exposures more than 30 seconds (15-20 max usually for me) the none plus backs are a great buy.
I know the dalsa-based leaf aptus 22 is hard-limited to 32 seconds through firmware, it is also only ISO25 which makes it a little bit limiting for my type of photography. The P25 is ISO50 and some P25 users apparently make a couple of minute exposures successfully if it is cold enough, so I guess there's no firmware-imposed limit on the P25 then?
 

gazwas

Active member
Shot way back in 2006 and dug out of a folder of random images on my studio computer I found this image taken with a P25. With some time spent in C1, I'm sure this image could be improved on really easily.

Shot under very strong late winter afternoon sunlight and a difficult colour for any back to get without clipping but the P25 without all of those fancy opticolor etc stuff holds up very well IMO and I wouldn't hesitate to shoot a paid job with one tomorrow.
 

gazwas

Active member
I know the dalsa-based leaf aptus 22 is hard-limited to 32 seconds through firmware, it is also only ISO25 which makes it a little bit limiting for my type of photography. The P25 is ISO50 and some P25 users apparently make a couple of minute exposures successfully if it is cold enough, so I guess there's no firmware-imposed limit on the P25 then?
Can't answer that question sorry as I mainly shot around the 15-20 seconds max with any of my cameras. Very long exposures is a pretty specialist field IMO and I would never have the option to shoot a 20min exposure followed by a 20min dark frame (40mins) on any job due to time restraints and budget.

Nice feature if you really need it but not a deal breaker on well priced non plus back. Do you often shoot very long exposures or is it one of those things on your shopping list from listening to photographers/forums discussing this?
 

torger

Active member
Nice feature if you really need it but not a deal breaker on well priced non plus back. Do you often shoot very long exposures or is it one of those things on your shopping list from listening to photographers/forums discussing this?
No, I'm not that much of a long exposure guy, so I was actually shopping around for a second hand Aptus 22, but then I did some math. I currently shoot landscape on 5Dmk2, usually at f/8, always base ISO which is ISO100 for this camera. I went trough latest year's files and found to my surprise that there are quite many in the 5 - 20 second range, just before/after sunrise/sunset. The attached shot is one 15 seconds f/8 ISO100, polarizer filter (1,5 stop light loss I think). With the Aptus at ISO25 and my tech cam lenses which do best at f/11 that would become 2 minutes.

So I'm not after "long exposures" (at least not deal-braking, I do occasional 5 - 6 minute shots, but I can live without that for the entry level back), but since I lose one stop in sensitivity (ISO100 -> ISO50), and one stop in aperture (f/8 -> f/11), and possibly a stop more in center filter, 30 seconds limit can be a bit tight, just upping to 2 minutes would make a significant difference for me.
 

dougpeterson

Workshop Member
There is no firmware imposed limit on a P25 non plus. Technically you could take a 2 minute, or even 20 minute exposure if you wanted to. However quality degrades very severely after 30 seconds. Cold ambient temperature helps, but not that much.

You need a P45 or a P20+, P21+, P25+, P30+, or P45+ or an IQ180. Those are the only Phase or Leaf backs which can hit 2 minutes. A P25 will not.
 

torger

Active member
Yeah, I'll think about it. When one goes from DSLR to MFDB as I do one has to sacrifice certain type of pictures which MFDBs simply cannot do. I may get used to the thought that long exposures can't be done and save some money.

It is probably wiser for me to get a P25 or even Aptus 22 now and live with the limitation and keep an eye out for a good P45 or P45+ deal in the future. I did not get a tech camera with high resolving power lenses to insult it with a 22 megapixel back for longer than I need :). I believe the typically rather high P25+ price will drop significantly in the coming year so it is not an ideal investment for an amateur like me that intend to upgrade soonish.
 

richardman

Well-known member
Ray, thanks.

I owned a P30 back for a while so I know it's not compatible with the wide SWC lens. I didn't realize that it's the only one :) Just my luck.

Anyone who has a spare P25 or Leaf equivalence in V mount please let me know (will post it at the FS/WTB forum too)
 
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