[cream puff]

as the title states, i have my first projector (an optoma hd20) on the way.. I didnt want to spend an arm and a leg on my first projector until im sure i like it.. the only major knock that really concerns me on these entry 1080p projectors is black level, and i saw on a thread here about the epson 705 hd that they use ND filters to improve the black levels..


wondering what size you guys reccomend for the HD20 and what results if any anyone has experienced.

 

[Donny Bahama]

Please edit your post and link the thread you mentioned (for those of us who've never heard of ND filters and want to get some background knowledge.)

 

[Sheridan1952]

My first question would be...how are the black levels in a totally dark room? ANY light will have a negative impact on the image.

 

[cream puff]



Quote:
Originally Posted by Donny Bahama /forum/post/20808882


Please edit your post and link the thread you mentioned (for those of us who've never heard of ND filters and want to get some background knowledge.)

i dont have the exact post handy, but it was in the epson 705 hd owners thread iirc..

Quote:
Originally Posted by Sheridan1952 /forum/post/20808989


My first question would be...how are the black levels in a totally dark room? ANY light will have a negative impact on the image.

will have to report back after it gets here (monday) was hoping someone would have some input so i can get a filter bought off ebay and have it show up here around the same time as my screen (about 10 days out)

 

[Sheridan1952]

You can try it, I'm only saying that the blacks are only as good as how the dark the room is. As an illustration, I'm including the link to another person's website where he clearly shows the effects of ambient light on a screen.

http://www.avintegrated.com/lighting.html

 

[1am7h30n3]

yes lighting has a huge impact on black level... but, with my current dlp projector, you can have a small amount of light in the room and you can still see the "gray" blacks, as in, the black level can't go darker than that.


I have considered an ND filter, but never actually got around to trying one, I think I would be willing to live with the compromise of slightly lowered brightness for slightly lowered black levels.


Please post back on your results if you do try it!

 

[cream puff]



Quote:
Originally Posted by Sheridan1952 /forum/post/20809542


You can try it, I'm only saying that the blacks are only as good as how the dark the room is. As an illustration, I'm including the link to another person's website where he clearly shows the effects of ambient light on a screen.

http://www.avintegrated.com/lighting.html

good info in that link, while the room is totally light controlled (can be pitch black, ie batcave).. there will be times when there is some ambient light on (sports or games with people over, or if i just dont feel like sitting in the dark)


so the plan is to remove the ND filter when you go to 'bright' mode, and put it back on for movie in the dark mode..


ordered one on ebay for 9 bucks, so if i hate it its not like it was a big expense, will post results once its here

 

[dswdallas]



Quote:
Originally Posted by cream puff /forum/post/20812204


good info in that link, while the room is totally light controlled (can be pitch black, ie batcave).. there will be times when there is some ambient light on (sports or games with people over, or if i just dont feel like sitting in the dark)


so the plan is to remove the ND filter when you go to 'bright' mode, and put it back on for movie in the dark mode..


ordered one on ebay for 9 bucks, so if i hate it its not like it was a big expense, will post results once its here

Make very sure its a glass lens and not a plastic lens. The lamp generates a lot of heat and could melt a plastic lens.

 

[cream puff]



Quote:
Originally Posted by dswdallas /forum/post/20818433


Make very sure its a glass lens and not a plastic lens. The lamp generates a lot of heat and could melt a plastic lens.

i did, and its a glass.. in the above thread i mentioned where i learned of the 'trick' guys had plastic ones that had hot spots melt in them and the picture got all fuzzy lol

 

[conradjohnsonfan]

not an ND filter, but I have been using a 81EF warming filter on my HD20. Lowers the black level, and with a color calibration to compensate for imbalance, there is a noticable increase in contrast without sacrificing too much brightness. I have calibrated two modes. One for cinema viewing in a dark environment, and one for bright viewing with some abient light present.



So far I am liking the results...

 

[goneten]

Any pics ?

 

[cream puff]

alright guys have everything all set up and the ND filter came in today.


optoma HD 20, 120 inch matt white screen (a cheapo one)


calibration per the avs HD 20 user thread.


pic is with my iphone at about 6 ft from the screen, no processing done to the pic other than cropping.. left the image a little bit 'off' so its easy to tell where the split is.


I am VERY happy with how the ND filter improved the blacks, went from obviously grey, to very nearly black and only a little grey if you are 'searching' for it in a almost all black screen, considering I have white walls and roof, I dont think you can do much better without changing the room itself..



heres a pic showing the change, the nd4 is a little too dark for this projector, made the image look a little 'flat', where with the ND2 the picture looks almost identical in bright screens and grey.. just took a little bit of the punch out of the bulb making the blacks blacker.. optoma HD20UB? lol

 

[p_sousa]

very very nice indeed, but where did you buy that?

 

[cream puff]

ebay, they are like ~10 bucks.. just gotta make sure its glass not plastic

also any camera shop would carry them if you want to buy local

 

[p_sousa]

in black the nd filter seem working amazing but how about other colours? can you take some pics in a movie with many colours to see how they appear with nd filter?

 

[jamnperry]

What size for the optoma? I want to try this!

 

[airscapes]

Quote:

Originally Posted by p_sousa in black the nd filter seem working amazing but how about other colours? can you take some pics in a movie with many colours to see how they appear with nd filter?

For those not familiar with what neutral density filter does, it just reduce light output equally across the visual spectrum.. assuming it is a quality filter. If the quality is low, it will effect color. It is just like sunglasses for your projector.. This is the same principle an iris works on, reducing the light output so the bright areas of the screen do not was out the neighboring dark areas.

 

[p_sousa]

thanks for the explanation

 

[johnsmith808]

Quote:

Originally Posted by conradjohnsonfan not an ND filter, but I have been using a 81EF warming filter on my HD20. Lowers the black level, and with a color calibration to compensate for imbalance, there is a noticable increase in contrast without sacrificing too much brightness. I have calibrated two modes. One for cinema viewing in a dark environment, and one for bright viewing with some abient light present. So far I am liking the results...

Okay, now you are taking filters to the next level. Not just reducing both peak white and black floor. Where do you purchase these filters? How do you calibrate colors?

 

[Captain McFunk]

What size filter for the Hd20 PLEASE??????