Jump to content
UltravioletPhotography

Infrared Panorama


Recommended Posts

bostwickenator
First real test with the modified NEX-5, Hoya OG filter to generate the IR in the blue channel. Shot with a SEL5518Z lens.

post-303-0-69060500-1592442434.jpg

Link to comment

Ulf, It could be a range of OG, depending on wb, camera, etc., not everyone will get the same thing using the same filter, other factors influence the outcome, processing, swapping...

Hard to say, he will know the exact filter.

Reminds me a lot of what I get using 570nm (RG570). Only one type of tree here, Oaks (Oak Savanna), so no tree color delineation here .

 

post-87-0-33836600-1592461620.jpg

Link to comment

Steve, You are naturally right, but are also speaking as a filter specialist.

Hoya's filter glass program ha a range of different OG-filter glass types, with different cutoffs.

 

However Hoya's photography branch has very few orange filters.

The O (G)- and the YA3-filter are the ones I find with a quick search.

 

I assumed, possibly incorrectly, that the filter was an orange standard Hoya photography filter from some photo dealer, as bostwickenator didn't specified it better.

 

Nice pictures by the way.

I really like images with dramatic clouds and their shadows.

Link to comment
bostwickenator
Steve you are correct this is the Hoya O(G). I did actually reference your chart Ulf W it was extremely useful after I figured out why there were various numbers of lines of each color. The harder edge on this Hoya seemed to make it a very nice low cost option to get a nicely independent IR channel. As for the location this is a tributary of "Lake" Travis just to the west of Austin, TX but I wish it was Weymouth. I think the majority of the trees are Cedars but I'm no arborist.

post-303-0-64299400-1592580075.jpg

Link to comment

Bostwickenator, I wasn't right about the O(G), you were. :-) I have seen the O(G) in eBay, but I don't know which Schott OG filter it is close to exactly.

I am not sure this filter is made anymore, I see it used, but I see it no longer available (for example) on B&H:

https://www.bhphotov...ange_G_HMC.html

 

Keep in mind Hoya doesn't make Hoya camera filters, they are made by another company which uses the Hoya name on the filters they make using Hoya filter glass,

however they don't use the Hoya Optics filter glass name for the camera filters.

 

Just like Schott, Hoya Optics makes more than one orange longpass filter, these are their longpass filters between 500nm and 600nm.

 

Here is the Hoya Optics longpass filter lists.

They make two types, and frankly, I am having a hard time seeing the difference, other than they show one list as a T graph and the other list as a Ti graph.

 

https://hoyaoptics.c...filter-l-y-o-r/

 

https://hoyaoptics.c...lters-w-series/

 

All Hoya filter glass types:

https://hoyaoptics.c...-glass-filters/

Link to comment

Not to bore anyone, but here are some overlays.

Keep in mind, all plots here are using 3mm thick filter glass, to stay the same as the Hoya data, but in real life, most camera filters don't use 3mm thick glass, usually something closer to 2mm.

 

First, the two Hoya longpass filter types, "Sharp Cut Filters (L,Y,O, R)" vs "Sharp Cut Filters (W)":

(keep in mind the L,Y,O,R types are shown as T and the W types are shown as Ti)

post-87-0-70783800-1592596746.jpg

 

 

Next is a comparison between the Hoya W types and the Schott OG longpass types (515nm - 590nm, orange filters), both are Ti, so these are quite directly the same.

post-87-0-02774600-1592597055.jpg

 

 

Here is the Hoya L, Y, O, R types compared with Schott OG filters (515nm - 590nm, orange filters).

Keep in mind again the Hoya filters in this comparison are T and the Schott filters are Ti.

post-87-0-09965200-1592597227.jpg

Link to comment
  • 2 weeks later...

It took me a while to find this topic again.

I got a Hoya O(G) filter.

To the eye it looks about half way between Schott RG530 2mm and Schott RG550 2mm.

Here is a photo. 530nm left , O(G) center, 550nm right.

I have not compared them photographically yet.

Given the visual comparison it looks like Hoya O(G) is made from Hoya O54, but 2mm instead of the 3mm that the graph shows, because 2mm is the more usual camera filter thickness,

which would lower the transmission slightly, thus putting it in the 540nm - 550nm range, so between 530nm and 550nm. Just an eyeball guess.

Oh, wait, let me measure the Hoya O(G) thickens with my fancy new micrometer! Just got this new micrometer, now where did I puit that?

Hoya O(G) =1.96mm AKA 2mm thick like I expected.

Or, it might be the Y58 glass, hard to say.

 

post-87-0-12469700-1593651353.jpg

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...