First DCG, Please, Help me find the problem.

This is a forum to share experiences and ideas about holography.
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Kiffdino

First DCG, Please, Help me find the problem.

Post by Kiffdino »

Hi guys,
long time since my last post.
anyway yesterday night i started my first two DCG exposures and well, i got nothing.
thats always happening to me when i try something new in holography it doesnt work out.
10 hours of setting up, exposing and developing for nothing...
please help me find the problem:

my setup hasnt changed since my successful silver halide work, still denisyuk setup with object ontop of film (distance 2 cm).
new green laser 315m though (100mw)

i sticked very close to the instruction given in the wiki:

-i coated using veil coating.
-let the plate dry for aprox. 3 days in a cool room. open window so outside temperature maybe 5-10°C

-mixed the G307 formula (0,5g glycerin 100% , 0,3g aluminum sulfat anhydrous 51-59%, 5g potassium dichromate, 100ml water) and cooled it down
-switched redlight on
-sensetized the plates for 30 sec
-wiped the back and dryed each plate with hairdryer cool setting for 1 minute
-put them all in a light and airtight box
-turned on the laser
-let the whole table rest for 5 min and exposed 20sec
-let plate in position fordark reaction 5 min (red light was on though)
-put the plate in the oven for 2 min at 100°C
-took it out and cooled on a metal plate for 1 minute
-put it in a first DI waterbath to wash out dichromate for 3 min
-then second bath for 3 min
-switched on a halogen light shining on the plate while blowing with a hairdryer on cool setting for about 1 minute on it until it seemed dry.
put the plate in a 70% Isopropyl alcohol bath for 15 sec, then quickly in 90% Isopropyl alcohol for another 15 sec, then 2 min in a 99% Isopropyl alcohol HOT bath.
-then i felt quite dizzy, beacause of all the alcohol in the air ;-)
-the wiki quoted that i should be able to start seeing something in the 99 percent bath, i saw nothing
-well already disappointed i took the plate out of the bath an dried it for about 3 min with a hairdryer at maximum heat and power very colse to the plate.
-there was nothing. The Plate looked just perfectly clear expect a slight yellow stain from the dichromate.

thinking to myself that the problem might be due to underexposure i repeated the same process exposing for 160 seconds (2min40)
same result.

very disapointed i went to sleep.... :(
How vulnerable is DCG to agitation during exposure. I build a table with innertubes and it worked out fine for silverhalide work, but im still living in an appartment house so vibration is always my concern. Long DCG exposure times could be problematic.
i attached two pictures showing my poor results. (actually they show nothing, but thats all i got)

have a nice day
Attachments
first exposure 20 sec
first exposure 20 sec
exposure 20sec.jpg (38.34 KiB) Viewed 14816 times
second exposure 160 sec
second exposure 160 sec
exposure 160sec.jpg (38.47 KiB) Viewed 14817 times
dave battin

First DCG, Please, Help me find the problem.

Post by dave battin »

Kiffdino, well even if you didnt get results, you get an"A" for effort. i usually suggest the first time DCG's use standard dcg processing first time around ,using the g307 formula can be VERY challenging. can you get your hands on some kodak rapid fix. you will find that many here will give you advise on how to use this G307formula(even tho the have not used it sucessfuly themselves), you will be confused as to which way to go. again i would recommend you to start with the rapid fix to get you going ......then switch over to the g307 formula.

for a safe light i simply use a floresent light with some yellow film wrapped around it. or even a yellow "bug" light works well.
dave battin

First DCG, Please, Help me find the problem.

Post by dave battin »

after you sensitized the plate how long did you allow the plate to dry?
Hans

First DCG, Please, Help me find the problem.

Post by Hans »

-let the whole table rest for 5 min and exposed 20sec
-let plate in position fordark reaction 5 min (red light was on though)
-put the plate in the oven for 2 min at 100°C
-took it out and cooled on a metal plate for 1 minute
-put it in a first DI waterbath to wash out dichromate for 3 min
-then second bath for 3 min
-switched on a halogen light shining on the plate while blowing with a hairdryer on cool setting for about 1 minute on it until it seemed dry.
put the plate in a 70% Isopropyl alcohol bath for 15 sec, then quickly in 90% Isopropyl alcohol for another 15 sec, then 2 min in a 99% Isopropyl alcohol HOT bath.
-then i felt quite dizzy, beacause of all the alcohol in the air ;-)
Here's the mistake you made: The plate should not be dried before putting it into the alcohol baths. That collapses the fringe structure. Developing G307 is like with MBDCG a kind of balancing act. You must find the ideal temperature (27C for my gelatin) of the water wash at which the hologram will appear brightest after the last alcohol bath. If the water wash is too hot, the hologram will be milky.

The good news here is that you don't have to throw away your last plates. The holograms are likely still in there. Just put the plates into a water bath at 27C for about a minute and then into the alcohol baths. Then dry the plate with a very hot hair drier. Don't be discouraged if the plate becomes milky during drying. The milk will usually disappear during longer hot drying. If the exposure was correct a hologram should appear.
Kiffdino

First DCG, Please, Help me find the problem.

Post by Kiffdino »

hi dave,
well thanks for the compliment. I did not use fixer because i couldnt get it.
I even contacted Kodak and they said they wouldnt sell it in Germany so i chose the oven.
dave battin wrote: after you sensitized the plate how long did you allow the plate to dry?
About a minute drying it with a hairdryer on cool setting. It still seemed a little damp to me.
Hans wrote: The good news here is that you don't have to throw away your last plates. The holograms are likely still in there. Just put the plates into a water bath at 27C for about a minute and then into the alcohol baths. Then dry the plate with a very hot hair drier. Don't be discouraged if the plate becomes milky during drying. The milk will usually disappear during longer hot drying. If the exposure was correct a hologram should appear.
hi hans,
well thats good news that there might be some hope for my plates. thankyou.
So what you are saying is. The water baths for washing out the dichromate should have a temperature of about 27°C.
So after i wash the plate twice for about 3 minutes i put them immediatly in the first alcohol bath 70% for 15 sec then 90% for 15 sec and a hot 99% alcohol bath for 2min.
ill try that.
dave battin

First DCG, Please, Help me find the problem.

Post by dave battin »

Kiffdino wrote:About a minute drying it with a hairdryer on cool setting. It still seemed a little damp to me.
I would try to wait a hour (or more) after sensitizing your film, its not a good idea to force dry your plates as you can easly seal in moisture ..........
Kiffdino

First DCG, Please, Help me find the problem.

Post by Kiffdino »

okay next time i wait an hour
Kiffdino

First DCG, Please, Help me find the problem.

Post by Kiffdino »

well Hans i tried to do the developing process in alcohol again with the already developed plates but i didnt get a hologram.
The Gelatin seems very hard there is no milkyness at all except a small little strip at the corner.
So ill do the coating and processing again with longer drying times after sensetizing.
ill give you an update as soon as im done.
Martin

First DCG, Please, Help me find the problem.

Post by Martin »

Kiffdino wrote:well thanks for the compliment. I did not use fixer because i couldnt get it.
I even contacted Kodak and they said they wouldnt sell it in Germany so i chose the oven.
1) You don't necessarily need any fixer – potassium metabisulfite, sodium sulfite and alike will do the job as well.
2) In case you'd still insist on using photographic fixer, why not take a look there (http://www.tetenal.com/index_c.htm?AKT= ... 00070&L=UK)?
Hans

First DCG, Please, Help me find the problem.

Post by Hans »

hi hans,
well thats good news that there might be some hope for my plates. thankyou.
So what you are saying is. The water baths for washing out the dichromate should have a temperature of about 27°C.
So after i wash the plate twice for about 3 minutes i put them immediatly in the first alcohol bath 70% for 15 sec then 90% for 15 sec and a hot 99% alcohol bath for 2min.
ill try that.
Yes, that should do the job.
well Hans i tried to do the developing process in alcohol again with the already developed plates but i didnt get a hologram.
The Gelatin seems very hard there is no milkyness at all except a small little strip at the corner.
So ill do the coating and processing again with longer drying times after sensetizing.
ill give you an update as soon as im done.
If the gelatin is very hard, you can re-process again but with a higher water temperature. So, you can use the same plates again and this time immerse them in a 30C washing water, then immediately in the alcohol baths. If there is still no hologram, do it again but at a higher temperature. Once the temperature becomes too high there will be milkyness. If you find that at the higher temps you get milkyness, but no hologram there was something else wrong and no hologram was recorded in your emulsion.
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