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Best Red Filter (Physical or App) for iPad?

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#26 Lane

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Posted 15 November 2012 - 06:43 PM

I am going to use the Red Eyes from now on. What I like better, it is thinner and clings much tighter to the screen. The thicker Astro Gizmos film will not lay completely flat especially as it gets older and bent up a bit.

It also eliminates colors better than Astro Gizmos. I can still see blue through the Astro Gizmos film but not Red Eyes.

I can also keep the main screen at 100% so it matches the brightness of the bottom bar and Red Eyes darkens them at the same level, instead of the bottom bar always being brighter as it is with the Astro Gizmos simply because I have to keep the Sky Safari brightness at 50% to make it work well.

#27 Tom Polakis

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Posted 15 November 2012 - 11:50 PM

"Red Eyes not only dims the light, but it also diffuses it slightly."

I am going to have to strongly disagree with that statement.

I have been using Astro Gizmos for a while but decided to try the Red Eyes to see how it compares. It is definitely darker and takes away more of the color than the Astro Gizmos does. It does not reduce sharpness at all from what I can see. I am having no trouble reading the NGC numbers at all. If fact I think it may be the opposite, this film is thinner than the Astro Gizmos and may actually make things a bit easier to read.



Thanks for posting photos. I should have thought of that. In an episode of getting carried away with a project, I photographed the iPad running SkySafari with the two films, and then with the 1/8" red plastic that I use on my laptop in the field.

You are correct about the brightness. At f/4 and ISO 800, 4 seconds was about the right exposure with Red Eyes to bring the right tail of the histogram to the middle. The get the same histogram with Astro Gizmos, I had to reduce the exposure to 1.6 seconds, so it's more than one photographic stop brighter.

Since the brightness in SkySafari can be diminished to near invisibility even with the Astro Gizmos film, the density is not really that much of a concern. What both brands of films do is create muddy contrast. When I look at my laptop with 1/8" red plastic, the sky rendition in Megastar is nearly black with white stars. The films have the effect of a muted, red sky that messes with my dark adaptation too much. I wish there was a way to somehow adjust contrast in addition to brightness. So I held the 1/8 red plastic up to the iPad, and sure enough, it improves that view quite a bit.

My concern with the Red Eyes has been sharpness, and the photos confirmed that it's a problem, at least with the sheet I have. The embedded image in this post is a 100% scale crop, comparing both films. You can see the reduced sharpness with the Red Eyes film. Note that exposure is shorter with Astro Gizmos film to make the brightness comparable, but this has no impact on sharpness.

Comparisons of the films and laptop filters can be found in these photos.

Red filter tests for iPad

By the way, my settings that would be suitable for visual observing at a dark site would be iPad brightness all the way down, and SkySafari brightness at 50% with Astro Gizmos, or 30% with Red Eyes.

Tom

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#28 Lane

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Posted 16 November 2012 - 12:42 AM

If there is a difference in sharpness on mine, I can't see it. At any rate I can read the NGC numbers very clearly.

I am using IPAD 3 - are you using 2 or 3 ?

#29 Lane

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Posted 16 November 2012 - 12:51 AM

"By the way, my settings that would be suitable for visual observing at a dark site would be iPad brightness all the way down, and SkySafari brightness at 50% with Astro Gizmos, or 30% with Red Eyes."

I think you wrote that backwards, you mean 30% with Astro Gizmos and 50% with Red Eyes, since Red Eyes is darker.

#30 ThreeD

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Posted 16 November 2012 - 12:53 AM

Perhaps the best comparison photos for sharpness would be to set the brightness levels you would actually use which should then (hopefully) result in the same exposure for both the photographs.

#31 Tom Polakis

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Posted 16 November 2012 - 11:41 AM

If there is a difference in sharpness on mine, I can't see it. At any rate I can read the NGC numbers very clearly.

I am using IPAD 3 - are you using 2 or 3 ?




I am using an iPad 1. I'd expect that better resolution of the later model iPads to look cleaner.

Perhaps I received a bad sheet of the Red Eyes film. You would certainly see a difference between the two films that I have, as the photo illustrated.

You are correct that I reversed the SkySafari brightness settings: 30% for AstroGizmos and 50% for Red Eyes.

Tom

#32 Lane

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Posted 16 November 2012 - 03:23 PM

The NGC numbers are considerably sharper on the iPad 3 than they are on my iPad 2. That is the primary reason I gave my grand niece the old one and bought myself an iPad 3. I was having a hard time reading those numbers at night. So that could be the difference.

#33 Lane

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Posted 16 November 2012 - 03:26 PM

Perhaps the best comparison photos for sharpness would be to set the brightness levels you would actually use which should then (hopefully) result in the same exposure for both the photographs.


That is not possible, the screen becomes so dark that the camera requires a 30 second exposure to see it and of course that blurs the letters.

You will just have to take my word for it. On the iPad 3 there is absolutely no problem with sharpness under either of these products. It sounds like with the iPad 1 and 2 that Astro Gizmos may be better.

#34 Tom Polakis

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Posted 16 November 2012 - 04:40 PM

Perhaps the best comparison photos for sharpness would be to set the brightness levels you would actually use which should then (hopefully) result in the same exposure for both the photographs.


That is not possible, the screen becomes so dark that the camera requires a 30 second exposure to see it and of course that blurs the letters.



Actually, it is quite possible, and ThreeD's suggestion is a good one. A better pair of photographs would have used the same exposures for both products. The iPad was close to the brightness levels that you'd actually use (50%), and dialing it down to 30% would have increased the exposure time to about 8 seconds, not 30. Other than a minor increase in dark current, how would that blur the letters?



You will just have to take my word for it. On the iPad 3 there is absolutely no problem with sharpness under either of these products. It sounds like with the iPad 1 and 2 that Astro Gizmos may be better.



I showed with photographs that the Red Eyes film that I received blurs the screen considerably more than the Astro Gizmos film. The point of my original post was only to compare the two products. I am certain that the same comparison with the two films that were delivered to me would show similar blurring even on an iPad 3 display, despite it being intrinsically sharper than my iPad 1.

If you can't readily see the difference, all I can figure is that the Red Eyes film has changed for the worse since you received yours or mine came from a bad lot.

Tom

#35 wbb

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Posted 16 November 2012 - 08:02 PM

Tom, I don't think you got a bad piece of the Red Eye material. My piece is slightly diffused also, but I have no complaints on my iPad 2. There are a lot of members in my astronomy club that use the red eyes on their iPhones and iPads, and have never complained about any bluriness. But that does'nt mean you don't have an issue. It's all personal preference. Just saying that the red eyes is actual cling material and it comes slightly diffused.
Bill

#36 Jeff Morgan

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Posted 16 November 2012 - 10:46 PM

A better pair of photographs would have used the same exposures for both products. The iPad was close to the brightness levels that you'd actually use (50%), and dialing it down to 30% would have increased the exposure time to about 8 seconds, not 30. Other than a minor increase in dark current, how would that blur the letters?


Folks are putting a lot of thought into the proper exposure protocol for the comparison.

But really, isn't the naked eye impression what matters here? It sounds like Astro Gizmos is the way to go.

#37 Alvin Huey

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Posted 17 November 2012 - 02:55 AM

A better pair of photographs would have used the same exposures for both products. The iPad was close to the brightness levels that you'd actually use (50%), and dialing it down to 30% would have increased the exposure time to about 8 seconds, not 30. Other than a minor increase in dark current, how would that blur the letters?


Folks are putting a lot of thought into the proper exposure protocol for the comparison.

But really, isn't the naked eye impression what matters here? It sounds like Astro Gizmos is the way to go.


I respectfully disagree with AstroGizmos unless you have the iPad3 and only the iPad3...anything else is way too bright...unless you decide to use SkySafaris pro and only SkySafarisPro as it has it's own dimmer app...once you leave that app...be prepared to lose your dark adaption...even with three pieces on .

#38 Lane

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Posted 18 November 2012 - 06:55 AM

Either one works fine on the iPad3, but you can get things darker with the Red Eyes.

Here is a shot blown up to show the resolution - red eyes on top, astro gismos on bottom:

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#39 Tom Polakis

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Posted 18 November 2012 - 12:34 PM

Either one works fine on the iPad3, but you can get things darker with the Red Eyes.

Here is a shot blown up to show the resolution - red eyes on top, astro gismos on bottom:



Good photos, which show very little difference between the two. I need to start searching Craigslist daily for an iPad 3. That increased screen resolution must really help. I feel like I'm buying an iPad only as a platform for running SkySafari!

#40 LivingNDixie

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Posted 18 November 2012 - 02:02 PM

Either one works fine on the iPad3, but you can get things darker with the Red Eyes.

Here is a shot blown up to show the resolution - red eyes on top, astro gismos on bottom:



Good photos, which show very little difference between the two. I need to start searching Craigslist daily for an iPad 3. That increased screen resolution must really help. I feel like I'm buying an iPad only as a platform for running SkySafari!


I have thought about getting an iPad and Sky Safari was one of the major selling points! I have Sky Safari plus on my Mac Book and I love it. Sky Safari with Moon Atlas, Mars Atlas and Gas Giants you are set for observing.

#41 mountain monk

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Posted 18 November 2012 - 07:30 PM

Last year I purchased a iPad 2 for my wife. This summer I got an iPad 3 for myself. Both have Sky Safari. There is a big difference: iPad 3 is superior.

Enjoy the night sky.

Jack

#42 cstarks

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Posted 14 January 2013 - 02:56 PM

I have a new Ultrabook Twist by Lenovo running Windows 8. It can be used PC style or Tablet style (very cool). I loaded TS6 on it and can use the touch screen to invoke any TS6 feature, including a new one - dragging the image on the screem to a new location with one finger. Only problem is that the red film by AstroGizmos is practically pink compared to red acrylic. I'm searching for a film like the AstroGizmos, only darker, so that I can continue to use the touch screen features.

Charlie

#43 Sean Wood

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Posted 15 January 2013 - 10:42 AM

Not an Ipad user, I'm an Android fan myself.. BUT I thought I'd weigh in as far as filters/films for touch screen devices. I personally use the acrylic film you might use for wrapping gifts or baskets. You need to try it on a capacitive touch screen first though to make sure it's capacitive conductive, which can easily be done in store with just a corner of the roll peeled off and placed over your screen. If it registers your touch you're golden. I found a 20' roll at the local Dollar Tree for a buck. I just cut a piece of material lager than the screen and tape it taunt over my tablet and put it back in it's case, this also helps protect the device from dew accumulation. I've doubled it before and dimmed the screen further and still had decent touch results. When I'm done I just take it off throw it away and my tablet's back to clear screen for general use.






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