{"id":3667,"date":"2023-12-01T18:16:10","date_gmt":"2023-12-01T18:16:10","guid":{"rendered":"https:\/\/www.nachleben.org.uk\/skomer\/?p=3667"},"modified":"2024-01-24T12:53:17","modified_gmt":"2024-01-24T12:53:17","slug":"sensitometry-densitrometry-fun","status":"publish","type":"post","link":"https:\/\/www.nachleben.org.uk\/skomer\/?p=3667","title":{"rendered":"Sensitometry \/ Densitometry Fun"},"content":{"rendered":"\n

Table for ND filter set. Made up from only 3 gels. Half stop gels are sold by LEE. Can do 21 stop wedge strips then.<\/p>\n\n\n\n

filter #<\/td>stop<\/td># gels in
frame<\/em><\/td>		# gels in
frame<\/em><\/td>		# gels in
frame<\/em><\/td>		Optical<\/strong>
Density<\/strong><\/td>		%
Trans’<\/td><\/tr>
<\/td><\/td>ND0.3 <\/strong><\/td>ND0.6 <\/strong><\/td>ND0.9 <\/strong><\/td><\/td><\/td><\/tr>
1<\/td>1<\/td>1<\/td><\/td><\/td>0.3<\/td>50<\/td><\/tr>
2<\/td>2<\/td><\/td>1<\/td><\/td>0.6<\/td>20<\/td><\/tr>
3<\/td>3<\/td><\/td><\/td>1<\/td>0.9<\/td>12.5<\/td><\/tr>
4<\/td>4<\/td>1<\/td><\/td>1<\/td>1.2<\/td>6.25<\/td><\/tr>
5<\/td>5<\/td><\/td>1<\/td>1<\/td>1.5<\/td>3.12<\/td><\/tr>
6<\/td>6<\/td>1<\/td>1<\/td>1<\/td>1.8<\/td>1.56<\/td><\/tr>
7<\/td>7<\/td><\/td>2<\/td>1<\/td>2.1<\/td>0.78<\/td><\/tr>
8<\/td>8<\/td><\/td>1<\/td>2<\/td>2.4<\/td>0.39<\/td><\/tr>
9<\/td>9<\/td><\/td><\/td>3<\/td>2.7<\/td>0.19<\/td><\/tr>
10<\/td>10<\/td>1<\/td><\/td>3<\/td>3.0<\/td>0.09<\/td><\/tr>
11<\/td>11<\/td><\/td>1<\/td>3<\/td>3.3<\/td>0.04<\/td><\/tr>
12<\/td>12<\/td><\/td><\/td>4<\/td>3.6<\/td><\/td><\/tr>
13<\/td>13<\/td>1<\/td><\/td>4<\/td>3.9<\/td><\/td><\/tr>
14<\/td>14<\/td><\/td>1<\/td>4<\/td>4.2<\/td><\/td><\/tr>
15<\/td>15<\/td>1<\/td>1<\/td>4<\/td>4.5<\/td><\/td><\/tr>
16<\/td>16<\/td><\/td>2<\/td>4<\/td>4.8<\/td><\/td><\/tr>
<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr>
<\/td><\/td># gels in
frame<\/td>		# gels in
frame<\/td>		# gels in
frame<\/td>		<\/td><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Shutter speeds \/deimos control. Need to double check by shooting some hi-speed video on phone. <\/p>\n\n\n\n

<\/p>\n\n\n\n

shutter
angle<\/td>		<\/td>Deimos setting 1<\/td>Deimos setting 2<\/td>Deimos setting 3<\/td><\/tr>
<\/td>millisecs<\/td>640<\/td>340<\/td>250<\/td><\/tr>
<\/td>fraction (using above)<\/td>16\/25<\/td>17\/50<\/td>6\/25<\/td><\/tr>
170\u00ba<\/td><\/td>1\/2+ of a sec<\/td>1\/4+ of a sec<\/td>1\/5th of a sec<\/td><\/tr>
85\u00ba<\/td><\/td><\/td><\/td><\/td><\/tr>
42.5\u00ba<\/td><\/td><\/td><\/td><\/td><\/tr>
21.25\u00ba<\/td><\/td><\/td><\/td><\/td><\/tr>
<\/td>frames open\/HS
240fps<\/td>		140<\/strong> frames
(7\/12ths. 1\/2+ \/sec)<\/td>		66 <\/strong>frames
(1\/4+ \/sec)<\/td>		48<\/strong> frames
(1\/5th \/sec)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Owing to the hybrid and vernancular nature of my printer, the camera speeds are not set the same as on a proper Oxberry. The Oxberry printer head has 4 speeds set by a gearbox effectively. However, the faster speeds, say 4\/second will cause problems when used with Deimos speed 1. Thats because that camera speed is only 1\/2 a second so isnt fast enough to keep up!! Even though much ‘faster’ shutter speeds are possible on the camera by using the adjustable angle, the FPS speed is independent of this.<\/p>\n\n\n\n

There might be a case to rethink the master-slave direction in my system. Currently the projector is the master. It triggers the camera. It dictates the sequence. Is it possible to reverse this? Could the camera dictate? Then, if fast projector speeds are set, all it does is load a new frame quickly, but camera is always prioritised? Its interesting that it works either way. So its like two different modes. <\/p>\n\n\n\n

<\/p>\n\n\n\n

LUX IN GATE READINGS (only made 7 filters……..)<\/p>\n\n\n\n

(NB Because its not a probe meter, readings for lamp vary considerably. Need to devise registration method) <\/p>\n\n\n\n

Filter<\/td>T
2.5<\/td>		V
90<\/td>		Con’ Light
LED\/ 1M – LUX<\/td>		Printer – LUX<\/td>FF<\/td>OD<\/td><\/tr>
No filter<\/td><\/td><\/td>900<\/td>19000<\/td><\/td><\/td><\/tr>
#1<\/td><\/td><\/td>370<\/td>8000<\/td>2<\/td>0.3<\/td><\/tr>
#2<\/td><\/td><\/td>210<\/td>4200<\/td>4<\/td>0.6<\/td><\/tr>
#3<\/td><\/td><\/td>140<\/td>2700<\/td>8<\/td>0.9<\/td><\/tr>
#4<\/td><\/td><\/td>80<\/td>1600<\/td>16<\/td>1.2<\/td><\/tr>
#5<\/td><\/td><\/td>37<\/td>740<\/td>32<\/td>1.5<\/td><\/tr>
#6<\/td><\/td><\/td>21<\/td>420<\/td>64<\/td>1.8<\/td><\/tr>
#7<\/td><\/td><\/td>11<\/td>230<\/td>128<\/td>2.1<\/td><\/tr>
#8<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr>
#9<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr>
#10<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr>
#11<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr>
<\/td><\/td><\/td><\/td><\/td><\/td><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

<\/p>\n\n\n\n

Speeds expressed as % of full shutter. Open RED, closed Green. Speeds 1, 2 and 3.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\"\"<\/a><\/figure>\n\n\n\n
\"\"<\/a><\/figure>\n\n\n\n
\"\"<\/a><\/figure>\n\n\n\n

More on ND filters reading here<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Table for ND filter set. Made up from only 3 gels. Half stop gels are sold by LEE. Can do 21 stop wedge strips then. filter # stop # gels inframe # gels inframe # gels inframe OpticalDensity %Trans’ ND0.3 ND0.6 ND0.9 1 1 1 0.3 50 2 2 1 0.6 20 3 3 1 0.9 12.5 4 4 1 …<\/p>\n","protected":false},"author":1,"featured_media":3673,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19],"tags":[],"class_list":["post-3667","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-lab-activity","archive-loop-container"],"_links":{"self":[{"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/posts\/3667","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3667"}],"version-history":[{"count":44,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/posts\/3667\/revisions"}],"predecessor-version":[{"id":3730,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/posts\/3667\/revisions\/3730"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=\/wp\/v2\/media\/3673"}],"wp:attachment":[{"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3667"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3667"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nachleben.org.uk\/skomer\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3667"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}