Displaying blue photos on the forum

[Ueee]

Here is a pic of mine, also manipulated in MS Offices picture manager. I adjust Saturation +50, Contrast +25 and Brightness -25. Easier to get it right with the camera though....

[cba_melbourne]

Anyone got an idea how far over volt you can run say a car 12V headlight?
Would they be better on AC or DC?
Stuart

As a rule of thumb for 12V halogen globes (car headlights or dichroic downlights or projector lamps) lowering the voltage by 0.5V below rated voltage can nearly double life. Just remember whilst ordinary downlights are rated at 12.0V, car headlights are actually rated at the higher battery charge voltage of 13.8V. Increasing the nominal voltage by 0.5V will about halve live.

As an example, a professional use Osram decostar downlight bulb I am holding in my hand is marked on its package with a life of 3100h at 12V and produces 2200cd, the same bulb is rated for a life of 5000h at 11.5V whilst producing 2050cd. The Osram website has lots of additional information on their data sheets - you would be surprised how many different bulbs there are that look exactly the same and fit in the same downlight (at last count almost 100, with different price, different life, different light output, different wattage, different beam angle, different reflector coating, different color temperature.............). Chris

Edit AC or DC makes no difference as long as the RMS power stays the same. With one exception, in a strong magnetic field the filament acts like a solenoid coil and vibrates with 50 or 60Hz causing it to break in few hours - that is why in MRI rooms they always use DC for lights.

[Anorak Bob]

I had a play around with my camera this afternoon and found that camera angle influenced the outcome maybe more than the light source. The lighter photo was taken with light entering an east facing door a meter and a half away from the blued block and no fluorescent light. The darker photos were under fluorescent light. The camera was on auto everything, standard "as delivered" settings except for ISO which I'd wound back to 400.

I may have been a touch generous with the blue.

BT

[Stustoys]

Hi Micheal,
When it seems to work pretty well(even if a little on the ugly side)

Hi cba,
Thanks for that I'll have a play when I get a minute.

Stuart

[Michael G]

Ugly - well maybe it is, but they say that "form follows function". (Industrial designer's saying (form being appearance) - usually only remembered when they can't get get something looking as they want it to.)

One question that I do have for the assembled scrapers among us - both in Richard's pic and Ewan's pic (I'm ignoring Bob's because as he says the blue may be too heavy) the blue is showing a whole bunch of short lines. I was under the impression that they should be broken up as the ideal surface consists of discrete spots. Have I mis-understood? (the photos probably have been taken mid job anyway) This view probably comes from surfaces being described as "X spots per square inch"

Michael
(high contrast photos causing comment already)

[simonl]

One question that I do have for the assembled scrapers among us - both in Richard's pic and Ewan's pic (I'm ignoring Bob's because as he says the blue may be too heavy) the blue is showing a whole bunch of short lines. I was under the impression that they should be broken up as the ideal surface consists of discrete spots. Have I mis-understood? (the photos probably have been taken mid job anyway) This view probably comes from surfaces being described as "X spots per square inch"

Michael

Hi Michael,

It's my understanding that the required spots/inch is dependent on the use of the surface. Difference surfaces require different minimum number of spots/inch. Some require 8 - 10 some 12 and some 25 spots/inch.

I'm guessing that the shape of the spots may have a little to do with the tool being used and/or maybe to a certain extent, the individual who is scrapping?
Long skinny spots could be caused if a person only ever scrapped in one direction which would cause small channels and show the blue up as long streaks. Not that I'm suggesting this has been done on these occasions.
Perhaps the physical size and dimensions may play a part too. Long skinny sections are going to be inherently difficult to scrape. It may also have to do with the blue being used, how much and whether it's been spotted on CI or granite plate. One surface can be made to look different under different conditions. Then again, none of these may have anything to do with the nature of the spotting in those pics. Interested in Stu's comment and maybe Phil (Machtool) if he's reading...

Bob's photo of the block from the scrapping class looks very similar to mine..... Or should I say that mine looks very similar to Bob's but one thing I did notice in the scrapping class, no two people scrape the same way.

Simon

[Anorak Bob]

Ok, I'll have another go with less blue .

I knew Stuart posted many a blued photo in his thread on cross slide scraping https://www.woodworkforums.com/f65/cr...ml#post1490478 so I looked and found this which I thought was a pretty good example of an evenly illuminated example of blued scraping. So Stu what was the technique you employed?

csn.jpg

[Stustoys]

Hi Guys, not a lot of time this morning.

One question that I do have for the assembled scrapers among us - both in Richard's pic and Ewan's pic (I'm ignoring Bob's because as he says the blue may be too heavy) the blue is showing a whole bunch of short lines. I was under the impression that they should be broken up as the ideal surface consists of discrete spots. Have I mis-understood? (the photos probably have been taken mid job anyway)

As I understand it, It doesnt matter until you have full bearing and are pretty much finished, then you start to be a little more fussy and split all those lines/big spots.

Interested in Stu's comment and maybe Phil (Machtool) if he's reading...

Think you might have that backwards

I knew Stuart posted many a blued photo in his thread on cross slide scraping https://www.woodworkforums.com/f65/cr...ml#post1490478 so I looked and found this which I thought was a pretty good example of an evenly illuminated example of blued scraping. So Stu what was the technique you employed?

Now thats a bit of a problem, thats in the shaper, there is an 8" tube near by. I assume its a fluro? (though I'm not 100% on that, if I recall correctly there is only one terminal each end which I would have thought ruled out fluro, came with the house 23 years ago). Having said all that, I have some LED spot lights and a circle fluro on my magnifier that could have been in use....... so not a lot of help sorry.


Stuart

p.s. I should get some time this evening to have a play...though daylight will be a problem. Also BT I think most the "problems" might be from trying to get pictures on longer ways. That would make defuse light more important right?

[Abratool]

I had a play around with my camera this afternoon and found that camera angle influenced the outcome maybe more than the light source. The lighter photo was taken with light entering an east facing door a meter and a half away from the blued block and no fluorescent light. The darker photos were under fluorescent light. The camera was on auto everything, standard "as delivered" settings except for ISO which I'd wound back to 400.

I may have been a touch generous with the blue.

BT

Bob
I was reminded in seeing your beaut scraped cast iron piece of the good time we all had at the April 2012 Scraping School.
Learnt a lot & had a great time with a bunch of like minded blokes.
Good to see the blueing you have achieved on the block.
regards
Bruce

[Stustoys]

Well I had a play during the day and evening(as there are to many windows on my garage) and without boring you with 100 pictures I'll give you the short version.

Long shots with zoom seem to be the winner.

Outside is of course the winner though the angle the picture is taken from still has a lot to do with it.
The color of the background seems to make a difference(at least to my eyes, leaving the camera on auto).

Inside its all about how much light, its diffusion(?) and angle, followed by camera angle.
The type of light and camera settings for different light seem to make little difference.
I didnt try a different background.

Maybe if you were after the best possible picture and you had 1000W of halogen lights it would be an improvement but I only have about 50Wx2 bare bulbs(or 200X of LEDs, I had 20W I think).

So in answer to BT's question of my technique. It would seem blind luck was employed and I assume I kept taking pics from different angles until I had one that looked right.

Stuart

[.RC.]

Here is a picture of canode blue on some Turcite that I bought from Marko..

It is the saddle of Pinky..

I found I had to apply the canode heavier then I would have had I been spotting cast iron..

Something of a different colour would have been better... I tried yellow canode, but it turned green.... white would have been good I think..

[Anorak Bob]

Here is a picture of canode blue on some Turcite that I bought from Marko..

It is the saddle of Pinky..

I found I had to apply the canode heavier then I would have had I been spotting cast iron..

Something of a different colour would have been better... I tried yellow canode, but it turned green.... white would have been good I think..

It might be water under the bridge Richard as far as Pinky's saddle goes but a thread on Turcite and your of it would surely be interesting to me and a few others. Phil F exposed us to the stuff at the last scraping class, a follow up would be great.

Bob.

[Stustoys]

Shouldn't be hard to make in any color you can get grease in?
Would a clearish base work? Vaseline seems cheap enough, comes in a handle container and its good for the skin

I havent even tried yellow yet lol


Stuart

[Michael G]

It's the thinness of the spotting compound that seems to be the problem rather than the colour. The latest thought that I had was to find a pigment that had a UV trace in it (that is, something that fluoresce under UV light) and see if that helps. You would need to scrape under a UV light source though.

I think Vaseline has been tried as a carrier for pigment but did not work that well

Michael