Support our Sponsors, they keep FADU free:   AG Photographic   The Imaging Warehouse   Process Supplies   RH Designs   Second-hand Darkroom Supplies  

Notices

Go Back   Film and Darkroom User > Equipment > Darkroom

  ***   Click here for the FADU 2015/2014 Yearbooks   ***

Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 3rd November 2021, 07:36 AM
snusmumriken snusmumriken is offline
Friend
 
Join Date: Oct 2021
Location: UK
Posts: 177
Default

Quote:
Originally Posted by Terry S View Post
I've done this myself Molli, not knowing that I shouldn't (apparently...)
And after reading the full post, I had to google the following questions, which I found interesting...

1. How do you get a bubble out of a thermometer?

Heat the thermometer bulb under hot, running water. Don't heat it too long -- you don't want the mercury or alcohol to rise to the top of the expansion chamber. Once the bubbles are gone, hang the thermometer with the bulb down for several hours.
I think that should be read literally. You don't want the liquid to fill the expansion chamber. The point of the chamber is to spread the liquid out so that the bubble can escape and the liquid rejoin. If the chamber is completely full, this can't happen. AFAIR, the break moves up the column quite quickly, so it shouldn't happen either.

The word 'pharmacist' caught my eye. I wonder if the advice not to finger the bulb relates to medical thermometers that will be placed in the patient's mouth? Would make some sense in that context, but puzzling advice in photography.
Reply With Quote
  #12  
Old 3rd November 2021, 09:55 AM
GoodOldNorm's Avatar
GoodOldNorm GoodOldNorm is offline
Friend
 
Join Date: Oct 2009
Location: Lincolnshire UK
Posts: 1,227
Default

Always stored my thermometers upright in a coffee jar half full of rice, never had a problem with separation or bubbles.
__________________
"Tea is surely the king of all drinks. It helps against the cold, it helps against the heat,against discomfort and sickness, against weariness and weakness". Heinrich Harrer.
Reply With Quote
  #13  
Old 17th November 2021, 09:11 AM
John King John King is online now
Friend
 
Join Date: Nov 2012
Location: County Durham
Posts: 3,319
Default Mercury Thermometers

I am hanging onto my last mercury thermometer for grim life because I know it is 100% accurate and always will be. (or as the advertising blurb said before I bought it accurate to within +/- .25 of a degree)
They never go out of calibration unless like some that get a bubble of air in the mercury column. (Yes I do store mine vertically that is the only way I can be reasonably sure it remains intact)

This one must be at least 30, possibly even 40 years old and I use it only for film developing which is done in the utility room so there is no problem with seeing the column.

I also have an electronic digital one which is for use in the darkroom and that compares almost exactly with the Mercury one. That is accurate enough for print developing both colour and B&W.
Reply With Quote
Reply
Support our Sponsors, they keep FADU free:   AG Photographic   The Imaging Warehouse   Process Supplies   RH Designs   Second-hand Darkroom Supplies  

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Removing the red window Svend Cameras - medium format 69 13th June 2016 12:06 PM
Removing water stains VickiB Monochrome Film 11 14th March 2011 09:48 PM
The Thermometer is back! RH Designs New products and offers 15 13th October 2010 09:43 PM
Conflicting thermometer readings Jeff Worsnop Darkroom 8 16th August 2010 07:58 AM
Strange 'Micro-bubbles' on film back surface. pentaxpete Ask Les 2 10th May 2010 12:24 PM


All times are GMT. The time now is 09:07 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.