4Sevens Quark AA-Warm Comparison Review

[Linger]

+1**
Wow VT., those are excellent. Your dedication in site selection, exemplified in the daylight control shot, is well rewarded with a superior result.
The first triple shot (smaller beam hotspots) makes for a great photo-study illustrating that 'cool' tints reflect more on the leaves. In a forest the cool-tint user can feel surronded by a wall of folige. The warm white in that picture shows more depth in the tree, revealing branches and trunks.
The triple beamshot also shows that the cool tints really do seem to glare off the leaves. The warm tint look softer and more accessible, like it's OK to take the dew-drop off its tip.

Your pictures turned out very well, better than my own attempts with other lights. That picture is a strong comment that cool is not the write tint for wilderness use.

 

[photonstorm]

Excellent pictures. Thank you for the reference.

 

[photonhoer]

Originally Posted by UnknownVT

The R5 Cool white to my eyes has always seem too cool/blue'ish and this beamshot seems to confirm it - and even though details are nice and sharp, when compared to the Warm or even Neutral white it seems paler/washed out and less vibrant in color - the Warm kind of looks too warm to me, and the Neutral white is a nice compromise.
...
BUT our eyes do not see like a camera with fixed daylight white balance,
and in real life it'd be a toss up whether I'd choose the Warm or Neutral White.

VT
This thread is a tour de force! You have provided enormously valuable information.

But, I have another context (than green leaves) to want to evaluate the warm LED: human flesh. My wife and I do medical volunteering all over the world, often having to provide our own light for surgery, biopsies, etc. One of the shortcomings of LEDs has been evaluating the color of human tissue, especially the shades of red in evaluating vascularity and inflammation. I first came across this problem at the BBQ, trying to visually establish the done-ness of beef or tuna — with an LED it all looks gray, you cant tell rare from well done. The same is true when trying to evaluate the color of tissue in a medical context.

I know this goes way beyond the call of duty, but any chance you could post some photos of the cool, neutral and warm LEDs on a partially-cooked steak of beef or tuna [sliced open to show the center] so I could get an idea how well we could use them in a medical context?

thanks, even if this is too much.

John

 

[kaichu dento]

I have another context (than green leaves) to want to evaluate the warm LED: human flesh.

My hand and foot are the first thing I check color on when evaluating tint. I still like to look at leaves, wood and other items, especially those that include any redness and have been pretty happy with my warmer tinted lights.

I think my 7x XR-E equipped Draco has better tint rendition than my E1e. :thumbsup:

 

[UnknownVT]

But, I have another context (than green leaves) to want to evaluate the warm LED: human flesh. My wife and I do medical volunteering all over the world, often having to provide our own light for surgery, biopsies, etc. One of the shortcomings of LEDs has been evaluating the color of human tissue, especially the shades of red in evaluating vascularity and inflammation. I first came across this problem at the BBQ, trying to visually establish the done-ness of beef or tuna — with an LED it all looks gray, you cant tell rare from well done. The same is true when trying to evaluate the color of tissue in a medical context.

I know this goes way beyond the call of duty, but any chance you could post some photos of the cool, neutral and warm LEDs on a partially-cooked steak of beef or tuna [sliced open to show the center] so I could get an idea how well we could use them in a medical context?

First, thank you for your kind words - there are very few occasions that I get access to steaks - beef or tuna - so the wait may be very long -

I do have - and I won't use "objections" - as that seemed to evoke emotional responses - even though strictly speaking it should be the correct word to use.

So let's just say "caveats":

Our eyes do not see like a camera - our eye/brain combination adapts to the lighting conditions which follows the Kruithof curve (a link well worth reading).

A flashlight is an oddity because of the way it is used - for some people it is the distant view that matters - in which case one sees that the actual illumination level is relatively speaking low - so a more yellow/amber light is more suitable. For close work where the flashlight may only be inches away - the illumination level could be quite high/intense - so we ought to prefer one that is closer to daylight color temperatures - ie: cooler/bluer.

Photographing leaves may seem to be "telling" but that is not the way we see outdoors - all the explanation etc well meaning and well done as they are - are merely an interpretation - mostly to be honest to fit in with the way we already think -

The triple beamshot on one photo is a very case in point. There was nothing extra that I could see from such a shot over the already posted matrix of separate shots (of exactly the same area of leaves) which in theory ought to be better and more accurate for comparison - but all of a sudden with the triple beamshot on one photo - some really great interpretations/descriptions/explanations were posted.....

I don't know how much of this was "emotive" :huh: to either "placate" me from my "objections", or just to prove that a triple beamshot on one photo is "better" over a matrix of separate photos - which it patently is not.
But, whatever, we did get much better interpretations/descriptions than any I had given so far....

BUT a caveat - I often do not go to this length in any explanation,
and hardly ever describe the photos -
because I usually leave (pun!) it to the viewers/readers to do that.
However I always make a point of how my seeing may differ from any photos presented.

Having given my caveats (and not "objections" )
I think I may still be able to give you a hand....

My hand and foot are the first thing I check color on when evaluating tint.

 

[lesur]

Thank you so much for the in-depth review, photos and the link to the Kruithof curve explanation. Now I'm at a cross-roads. Warm or not.....

 

[photonhoer]

Having given my caveats (and not "objections" )
I think I may still be able to give you a hand....

[...snicker...]

You are both too good and very kind! Thanks for the hand out. Our color interpretation circuitry sure did evolve in sun light, not LED light of any kind, didn't it!

I accept your unavailability of 'raw meat' and guess I'll have to put out a plea to borrow a cool white and a neutral white lamp to look into a body cavity or two myself. Any chance someone here would be willing to lend a couple of LEDs for a week or so?

MANY THANKS. That was indeed above and beyond....

John

 

[Xak]

I'm confused by the difference in beam profiles, as I noted in the Marketplace.

Since they are all XPGs in the same type of head, shouldn't they have the same beam profiles? Is it linked to the Cool, Neutral, Warm difference somehow?

I believe the "neutral" tints you are seeing is an older LED, not as bright, but a tighter hot spot. The "neutral white" quarks were available a few months ago. Not sure if they still are.

Rumor has it that if these "warm white" Quarks sell well he may sell "neutral white" Quarks with the newer R5 LED.

My neutral Quark is my favorite tinted light. Not quite so yellow as an incandescent, but noticeably better depth perception compared to my cool white LEDs.

I think the warm white would be optimal for the woods. I prefer my neutral for all around illumination, but prefer my cool white for urban settings.

 

[325addict]

OK, OK, very useful thread this, and now I just can't wait to get my hands on this one, it has been shipped already:

WARM WHITE Quark 123² Turbo

FINALLY a good, usable LED-light for in the woods? That would be the very first one... still can't believe it!

The proof of the pudding is in the eating, or something like that... if this one just performs NEARLY as good as one can see in the pictures, well.... the beginning of the end of the incan-era???

(and I just ordered four pieces of those monstrous FM1909 bulbs... and six AW IMR 18650s to power that 63 Watts(!) bulb...)

Timmo.

 

[fugleebeast]

I believe the "neutral" tints you are seeing is an older LED, not as bright, but a tighter hot spot. The "neutral white" quarks were available a few months ago. Not sure if they still are.

Ah, I know about the previous neutral run not being XPGs but I thought that UknownVT had some new XPG ones. Regardless though, shouldn't the Warm and the Cool have the same beam profiles since they are both XPGs? I'll put up the same picture that I did in the marketplace to show what I mean (crappy quality, sorry).

This picture was taken 10 inches away from the wall, my Warm Quark 123-2 compared to my Cool Quark R5 123-2. As you can see, the Cool has a much more defined hotspot and because of this, it throws much further. If we look at UnknownVT's pictures, it looks like his is doing the same. In the tree picture, the Cool Quark seems to have a tighter hotspot than the Warm. Since they are both XPG leds in the same heads, shouldn't the beam profile be the same?

I know that the Cool Quark will be brighter, because of the R5 flux vs the Q5, but I'm talking about the tightness of the beam, not the brightness.


Has anyone else experienced this? I'm just trying to figure out if all the Warm Quark heads will be like this or if it is a fluke. I personally like it, as the light is very floody. There are some people though, who may be expecting it to be exactly the same profile as their Cool Quarks.

 

[UnknownVT]

Regardless though, shouldn't the Warm and the Cool have the same beam profiles since they are both XPGs? I'll put up the same picture that I did in the marketplace to show what I mean (crappy quality, sorry).

Have you actually asked 4Sevens about this difference?

I pointed this out earlier in Post #23 (link) in this review
and even acknowledged your post (less than an hour after yours) in the MarketPlace in Post #399 over there too.

I would have thought the best person to do that would be the designer of these lights?

 

[fugleebeast]

I know you acknowledged it, thank you.

I haven't contacted 4sevens because I'm not planning on returning the light even if it is a fluke. Since some people here don't visit the Marketplace, I thought it was an interesting point to bring up here as well as there.

Since this thread is comparing the Warm Quarks to the normal Quarks, and since your example appears to be like mine, I thought it would be a valid point to discuss.

 

[UnknownVT]

I haven't contacted 4sevens because I'm not planning on returning the light even if it is a fluke. Since some people here don't visit the Marketplace, I thought it was an interesting point to bring up here as well as there.

Since this thread is comparing the Warm Quarks to the normal Quarks, and since your example appears to be like mine, I thought it would be a valid point to discuss.

So I contacted 4Sevens and got this explanation:

" It's very possible that the warm white phosphor is thicker or taller
just enlarging the single point of light. The larger the point, the
less focus from the parabolic "

Hope that helps?

 

[fugleebeast]

Vincent, thank you. I also contacted 4Sevens but haven't received an answer back. I had assumed that it might be something to do with the phosphor but I didn't know enough about LEDs to be sure. I appreciate all the work that you have put into this thread. Thanks again.

 

[lak]

VT
But, I have another context (than green leaves) to want to evaluate the warm LED: human flesh. My wife and I do medical volunteering....
but any chance you could post some photos of the cool, neutral and warm LEDs on a partially-cooked steak of beef or tuna [sliced open to show the center] so I could get an idea how well we could use them in a medical context?

So what's the verdict from those who own WW? Is it easier to see color variance in human tissue/skin/surface? I can't tell one way or the other from those hand beamshots.

 

[UnknownVT]

So what's the verdict from those who own WW? Is it easier to see color variance in human tissue/skin/surface? I can't tell one way or the other from those hand beamshots.

From a non-expert at this - but since I have all three tints in question I can try to give some input.

I thought at first I should be using something like the Medium level (3 = 22 lumens) but that turned out to seem a bit low.

I ended up comparing by eye at the Max or high levels.

This is what my eyes saw I still used the palm of my hand (no raw flesh at hand) -

Cool White seemed to make things look somewhat gray-ish and a slight tinge of green at the peripheries -
I can understand why many people do not like this for examining flesh tones.

Real incandescent (Streamlight Scorpion - xenon 2x CR123) palm looked pretty good with good separation of tones.

Warm White LED - very similar to the incandescent - with perhaps a tiny bit less red - but if I had not just used the incand I would not have noticed this.

Neutral White - you know I think I liked this the best - but remember I am nowhere near an expert, and may not be looking for/at the right things.

But my comparison with the real incand is accurate as I know how -
so if one is happy with incands for examination of flesh -
then the warm white most probably will do as well.

I know it's retrospective -
I do see all this in the hand palm beamshots.....

 

[NoFair]

Great review and thanks for taking the time to do the extra pics:thumbsup:

First thing I do with a light to check if the tint is good is look at the back of my hand in normal daylight and then illuminating it with the flashlight. If the hand still looks about the same then the tint is good.

I prefer neutral over cool and warm as well. Put a R2 xp-e in 4D tint in my Ti AA Quark and it is now my most carried light (it wasn't when it had a cool white R5 xp-g)

Sverre

 

[was.lost.but.now.found]

I'm going against the grain here, but personally (and I admittedly have poor color distinguishing vision) I think the cool white best reflects the true skin color.

 

[UnknownVT]

I'm going against the grain here, but personally (and I admittedly have poor color distinguishing vision) I think the cool white best reflects the true skin color.

Are you judging by eye in real life or by the palm photos?

If by the palm photos - then there is an explanation in order.

My beamshots are done with Fixed Daylight White Balance (sun symbol) - which is like comparing with sunny noon-daylight.

So the Cool White would be the closest in terms of white balance - and the warm white and incandescent will appear quite yellow.

However as explained our eyes do not see like a camera (with fixed daylight white balance) and emperically follows the Kruithof curve (please read).

In the absence of real daylight and having to use artificial light like a flashlight - examination of flesh tones is quite critical - incandescent have fulfilled this need for years -

This may on the surface not make any sense - since isn't incandescent light very yellow?

But the bias toward yellow and more importantly with good red content -
that may actually enhance our vision in distinguishing flesh tones -
ie: some of the colors may not be as accurate -
but we actually see better on the colors that do matter.

Whereas a cool white might be represented better when photographed - but in real-life it tends toward a grayishness without the vividness of the the incandescent.

These Warm Whites seem to imitate/mimic incandescent quite well - perhaps with very slightly less red - but they seem close to me - bearing in mind I am not an expert in this usage.

 

[GunnarGG]

@ photonhoer and lak

I work as an ophtalmologist and got my preon 2 ww yesterday.
The light that has been in my pocket so far is this incan:
http://www.medisave.net/fortelux-n-diagnostic-penlights-silver-p-739.html

I mostly use my flashlight for looking at the conjunctiva or skin around the eyes. Sometimes mouth mucosa and other stuff.

My view of LED tints so far is:

Cool white: not good
neutral white: it works but incan better
warm white: same as incan but has just tried it a couple of times

(This is at work. At home or outdoors neutral white is best IMO but the ww isn't that bad indoors, it mix well with other incandescent light indoors)

I noticed that the ww Preon was a tiny bit on the cool side compared to the incan but that might be that it is a little brighter (on low) and maybe the batteries in the incan was a little old.

I also check pupillary reactions but then tint doesn't matter.
One thing that does matter when you check pupillary reaction is beamprofile.
I want to be able to put the lightspot on one eye with no light on the other and then shift between the eyes. The preon (as most lights) has a lot of spill but the incan is more like a bigger hotspot with no (or very low intensity) spill.
The best for this task is the ophtalmoscope that has a cirkel with totally even ilumination so that is what I use when it is in reach.

I know that one of the Streamlight penlights have a little tube that you can put on the front and I will try to find something to put on the preon to reduce the spill.

What I have learned in the different threads about tint is that we have different opinions about it.
What I like you might dislike and vice versa, this is what I think...