Flocking evidence

[jambouk]

Has anyone ever seen hard evidence that flocking a tube which is already painted matte black reduces light scatter / improves contrast?

Jd

[Alien 13]

Hi Jd,

I suppose it would depend on how black the paint was some may look black in the visible spectrum but can be like a mirror at other wavelengths.

Alan

[jambouk]

Hi Alan,

But even so, have you seen any comparison data / imaging evidence of identical set ups with and without flocking, or pre- and post- flocking?

Jd

[Alien 13]

I have not seen evidence with a scope but have had tiny diffraction spikes on an image caused by poor paint used on a cheap adapter but that was exposing the base metal.

Alan

[nightfisher]

No evidence, but i flocked my TAL100 and it is a VERY sharp scope, great contrast, for what it cost it was worth doing

[sbooder]

I did once post a photo on here of my 10" half flocked to show the difference but I lost it when I changed PC and forgot to back up my astro folder with 6 years of pics on it.  but the point was that it showed light reflecting off the original paint and stopping dead at the flock.

And you can just see the difference when you first look through you flocked scope.

[jambouk]

I've flocked my Newtonian, but not convinced it made any difference.

I'm just surprised that for an intervention with such massive support, that no one has done measurements / imaging to prove it is a beneficial intervention.

Jd

[sbooder]

I've flocked my Newtonian, but not convinced it made any difference.

I'm just surprised that for an intervention with such massive support, that no one has done measurements / imaging to prove it is a beneficial intervention.

Jd

What did you use for flocking?

[jambouk]

Baking foil.

[jambouk]

Wilko's black flocking material.

Jd

[sbooder]

Baking foil.

Nice!  There are many materials used some use the stuff from FLO some use velvet, I use a different stuff to both of those.

[brantuk]

I remember Simon's post - it was irrefutable proof the tube was darker inside - even in broad daylight the results were stunning. As for measuring wavelengths of light - not needed - the visible spectrum was enough to see the reduction in light reflected around the OTA.

In fact - it was that post which convinced me to flock my 300P at the time.

[brantuk]

Baking foil.

I thought you used Baader Solar film James hahaha

[sbooder]

I remember Simon's post - it was irrefutable proof the tube was darker inside - even in broad daylight the results were stunning. As for measuring wavelengths of light - not needed - the visible spectrum was enough to see the reduction in light reflected around the OTA.

In fact - it was that post which convinced me to flock my 300P at the time.

I have tried to find it but with no joy.  I thought it might have been posted by someone else on another forum but No!  Never mind, I am sure I will flock another scope in the future and will post again.

[brantuk]

Check out post #4 in this thread:

http://stargazerslounge.com/topic/117928-skywatcher-250p-renovation-project/?hl=+flocking%20+250p

There's a pic half way down that post showing the effect.

[Cath]

Flocking certainly seemed to make a difference for my SCT, can't see why it wouldn't work for a Newtonian ..

http://stargazerslounge.com/topic/184511-flocking-a-6se/page-4#entry1922190

[jambouk]

The image looking up the tube is good, but I wish it had been flocked all the way to the top on one side to see the effect at the top; also the non-flocked side at the mirror end looks pretty dark and I can't see much light scattered; plus this is in day light.

The SCT thread again looks good, but still lacks a night time comparison.

As I say, I've flocked my Newtonian, but following a conversation with an astro-mate yesterday, it would be nice to see hard evidence this makes a difference at night.

James

[jambouk]

I thought you used Baader Solar film James hahaha

Have you seen the price of that stuff! It would be cheaper to line the 10" with gold leaf  

JD

[RikM]

From everything I've read it seems to be more of a potential improvement, just to be sure you are getting the best out of your scope that you can. Not a dramatic leap forward in contrast. I haven't flocked either of my Newtonians but I did have odd reflections off the bolt for my Dob knob. I coloured it black with a Sharpie marker and the reflections went away. When I have nothing better to do, I will flock my 6" and see what difference it makes but I'm not expecting a transformation.

[emadmoussa]

Ah - I've been contemplating flocking my 300P flextube. Apart from being scared like hell of taking the scope apart, I wanted a definite proof was going to improve contrast.

Would flocking the the top part only make a difference? I noticed most of the reflection happens around that area.

[brantuk]

Yes - I've seen a lot of dobs with just the top box flocked - sometimes with just with a patch of black felt opposite the focuser tube. There is definitely a small gain in contrast imho - but I've never gone to the length of measuring it. Wouldn't know how to lol.

[Peter Drew]

If your Newtonian has a white tube and you observe with both eyes open then it is worth painting or flocking a black patch opposite your non observing eye. This helps image contrast by darkening the signal from that eye. 

[emadmoussa]

Would chalkboard paint act similar to the flocking material?

[sbooder]

Would chalkboard paint act similar to the flocking material?

That is what most OTAs are painted with from new.  This still scatters light to a degree.

[sbooder]

If your Newtonian has a white tube and you observe with both eyes open then it is worth painting or flocking a black patch opposite your non observing eye. This helps image contrast by darkening the signal from that eye. 

It is worth doing on the outside of a black scope too, as although black they still tend to be shiny.