Testing sheet films - problems

rlfsoso · 2016-02-18T10:00:34+00:00

Hallo! Ich versuche mich gerade daran Ilford HP5 Planfilm (4x5) einzutesten, ich folge dabei der Anleitung von Dr. Beyer (vielen Dank für die Bereitstellung...

rlfsoso

Hello! I’m currently trying out Ilford HP5 sheet film (4x5), following Dr Beyer’s instructions (many thanks for sharing!): http://www.fotografie-in-schwarz-weiss.de/sw-fotografie/filme-eintesten/38-sheet films-eintesten.html Exposure with a Fujinon - W 1:5.6/210, f=11, 1/4 sec. through a frosted glass pane. Developed in a BTZS tube, HC-110 Dil. H. (1+63)@20°C for 10 minutes However, the first negative now presents me with a few puzzles (see below in the appendix): 1) I exposed according to the instructions (-5 stops of exposure compensation on my Profisix, measured through the frosted glass pane) Yet in the result, only Zone 2.5 reaches a density of 1.0 (offset = -0.9 !)? 2) Steps 16 and 16, which are duplicated on the Stouffer 31-step wedge, are actually quite different; you can see this with the naked eye on the negative Have I developed it far too briefly?! If so, what would be a more suitable starting point: 15 minutes? Many thanks, Rolf PS: I have already identified one possible source of error and will try to avoid it next time: For the BTZS tube I only need 60ml of developer; the Massive Developer Chart specifies a mixing ratio of 1ml to 5ml of water; 2ml to 118ml of H₂O would probably be better, as that’s less likely to go wrong.

Urnes

Try using a 1:31 dilution and start with the times given in the HP5 data sheet. That way, you’ll definitely end up with a standard deviation that suits your working method and needs. Is BTZS Tube a rotary developer? If so, it’s best to pre-rinse for another 5 minutes. https://www.macodirect.de/media/pdf/KHC11_datenblatt_d.pdf http://www.ilfordphoto.com/Webfiles/20106281054152313.pdf Ah, one more thing. Are you measuring with the Profisix on the camera’s ground glass? Is that right? If so, it must be calibrated to the focusing screen. And you may need to take the extension into account. I only have a very vague recollection that, if you want to measure with a fibre-optic guide on the focusing screen, you had to enter a correction factor on my Sekonic. Regards, Sven.

Renate

With the HC-110, there is a minimum amount of syrup that you shouldn’t go below. I believe there must be at least 6 or 7 ml of syrup per film. In 60 ml of dilution H, there isn’t even 1 ml of syrup. Insufficient density is usually caused by too little developer. The characteristic curve then dips in the mid-tones. HC-110 is very cheap. You shouldn’t skimp on it. ? ? Best regards ? Renate

rlfsoso

Hello Sven, Renate, thank you very much for your messages. € I took the measurements through the diffuser pane (frosted glass), through which I also took the photograph/performed the exposure. The step wedge was placed layer upon layer in the film cassette.€ € The "inventor" (or distributor: Fred Newman from the Viewcamera store) of the BTZS tubes explicitly states that no pre-wetting is necessary and backs this up with a series of tests and measurements. (There is a short YouTube video on this.) € The development times for HC-110 in Dil. B are a bit short at 5 minutes, hence the double dilution to arrive at less uncertain times. € In fact – measured against a 4x5 sheet – the absolute amount of developer is probably sufficient; [s]at least there is no indication on the relevant page for HC-110[/s] that one should use at least 6ml per 135 or 120 film. A 4x5 sheet is about a third the size of a 120 film. I’m not doing a stand development like with Rodinal, for example. For me, the main concern was whether I’d messed up the mixing because of the small quantities? € New film has undergone exposure; I’ll develop it again tomorrow and see how it looks. € R. [18-02-2016 17:22 minor corrections] € ]