Architeuthis

It is the Sony 20-70mm f/4 G lens. It is not of the highest optical quality (Sony labels such lenses with "GM"), but is regarded a decent performer... Here you can find serious over-water reviews of both Sony 20-70mm and the Canon 8-15mm. The reviews state that both lenses are very sharp (but one cannot directly compare the absolute values in lp/mm, since the Canon values were measured on a completely different camera/sensor): https://www.lenstip.com/643.1-Lens_review-Sony_FE_20-70_mm_f_4_G_Introduction.html https://www.lenstip.com/311.1-Lens_review-Canon_EF_8-15_mm_f_4_L_Fisheye_USM_Introduction.html My "ratings" of the UW performance of different lens/port/water contact optics combinations are based on dozends, sometimes hundreds of dives and are completely subjective. No test carts and/or measurements, motifs and conditions are always different. It is a pity that the companies that develop and sell domeports and water contact optics do not make their measurements/test chart photos, that they certainly have, accessible to the potential customers (I suspect they have reasons)... Here links to some UW photos I made with Sony 20-70mm and some other combinations discussed here: https://www.dpreview.com/forums/threads/sample-photos-from-sony-20-70mm-f-4-and-a7r5-uw.4724115/ https://www.dpreview.com/forums/threads/canon-8-15mm-fisheye-lens-with-sony-2x-tc-on-sony-a7r5-sample-photos-part-1.4779356/ https://www.dpreview.com/forums/threads/canon-8-15mm-fisheye-lens-with-sony-2x-tc-on-sony-a7r5-sample-photos-part-2.4779452/ https://www.dpreview.com/forums/threads/canon-8-15mm-fisheye-lens-with-sony-2x-tc-on-sony-a7r5-sample-photos-part-3.4779455/ No, I never used them. I could spot several WACP-1s at UW photography workshops and immediately was sure that I do not want to deal with such big staff (I find the "compact" WACP-C version already big and heavy enough)...

The initial statement “You cannot improve a lens’s in-air optical performance underwater.” is clear and true, but exceptions exist... (The Tokina 10-17mm fisheye lens behind a domeport, e.g., performs clearly better UW compared to the performance at the surface (especially when used together with a 0.71x speedbooster)...) Are optical jewels automatically performing better compared to, average quality, kit lenses for UW WA? Certainly not. Too many factors that ruin IQ UW ... An UW WA setup that would provide the idential optical quality, as an average kit lens provides on the surface, would be a true gem and a favorite for all of us... Already in the center the sharpness is diminished, just by the water (absorption and diffraction of the light), even when it is clear, not to speak about bad vis, to an extend that goes below the standards we are used on the surface. Not to speak about the corners that never can be sharp when using a domeport (or water contact optics) and the unpleasant distortions that (mostly rectilinear) lenses produce away from the center... The question is rather: what system, in combination, gives the least impaired results (lens/domeport combination, fisheye lens (with and w/o TCs), water contact optics/lens combination)? The lens itself is certainly a contributing factor, but it must not be overrated: A high quality WA lens that does not perform well behind a domeport can not reach the IQ of a kit lens in compination with water contact optics (e.g. because of a field curvature that is opposite to the curvature of the virtual image produced by the domeport; entrance pupil that makes correct positioning difficult). Another example is a 180° diagonal fisheye lens that, just because of the shortest object distance and hence minimal IQ detoriation produced by the water, gives way sharper images compared to a lens with considerably larger object distance... Only with lenses that work very well together with a domeport and in very clear waters one may be able to see differences that come from the lens itself. In my personal experience, the Sony 20-70mm and Tokina 17-28mm (Sony FF) and the Zuiko 12-40mm pro (Oly MTF), all behind Zen DP170, perform very well UW and give (subjectively) sharper images compared to Sony 28-60mm/WACP-C (FF), but only when conditions are at their best. The pure Canon 8-15mm fisheye comes close in sharpness to the Sony 20-70mm/DP170, but when used with TCs (Kenko 1.4x Teleplus HD pro DGX or Sony 2x TC) IQ is comparable to 28-60mm/WACP-C... As far as I know, none of these lenses provides the highest optical standards on the surface, but the Sony 28-60mm kit lens is certainly the least performing lens of them and a league below the others (Chip reports, however, that 28-60mm gives better results with WACP-1, hence 28-60mm/WACP-C is not the last rung in the ladder)... Wolfgang

When the discussion comes to Kenko TCs for Canon EF mount, one must say that there exist TWO versions of both 1.4x and 2x TC: the "Teleplus HD DGX" and the "Teleplus HD pro DGX"... I have the Kenko Teleplus HD DGX 2x TC version and used it few times with the Canon 8-15mm on Sony A7R5. Unfortunately, the IQ suffers a lot with this TC (too much for my taste). In comparison the Kenko Teleplus HD pro DGX 1.4x TC works very well with this fisheye lens (for me and that is what also several others reported here)... I do not own the Teleplus HD pro DGX 2x TC, but in the tread linked below, Massimo ("guest") has tested it and found that it worked very well (maybe comparable to the Sony 2x TC, that can be used on Sony cameras together with the Canon 8-15mm with sufficient quality):

The occasion to have two macro lenses with different focal lengths at the same dive looks very tempting (but what about the often quoted "dedicated mindset" of the UW photographer 😄?). I have some questions, especially to people who use MFO-3 with Sony 100mm GM. According to Nauticam, the empirically measured FOVs, for objects at macro distance, behind planport are 24° without (corresponding to approx. 100mm) and 40° with MFO-3 (corresponding to approx. 60mm focal length)... #1.: How is the IQ of the 100mm lens & MFO-3 compared to a pure macro lens with shorter focal length, e.g. the Sony 50mm macro lens? #2.: What about using the MFO-3 together with the lens, when 1.4x, or even 2x, TCs are attached (I guess since the TCs already by themselves degrade IQ to some extend, MFO-3 makes it even worse?)? Thanks, Wolfgang

When the fisheye/domeport positioning is corrct, there is no reason why the sample images between UW and on the surface should be different. If not, not only optical flaws, but also barell- and pincushion distortion will be pronounces/enhanced, depending on how wrong the positioning is... Here a link to some samle photos taken with the 7-14mm fisheye lens: https://www.dpreview.com/products/canon/lenses/canon_rf_7-14_2p8-3p5_fisheye_l_stm/sample-photos

One can snorkel with whalesharks also in Tansania/Mafia island, near the delta of the Rufiji river. I have been there 2024 and 2025. On one excursion it was approx. 15 individuals. The excursion with the least whalesharks was 3 individuals. Several boats with snorkelers are usually present, but the activity was still o.k. (maybe one dozend of snorkelers around)... I returned on Sunday, 29.3. from the Maledives (Omadhoo island in Ari Atoll). Also there whaleshark excursions are offered, also from other close islands and resorts. According to divers, who have participated, at these spots there are around appox. 150 snorkelers plus several groups of scubadivers UW, producing a lot of airbubbles. We gratefully declined from participation in such an excursion... Wolfgang

My monitor is able for Adobe RGB and the water looks nicer when I view and process in Adobe RGB. Since my main device for viewing (a 2K projector) and internet are not able to display Adobe RGB correctly, I process and store all photos in sRGB (with few exceptions, when I know that the output will be in Adobe RGB). Also this photo is entirely sRGB...

I have Weefine 2300 (branded as Kraken in US). It comes with "Auto shut Off" function that shuts the light off during flash.. I put it to the housing (Nauticam Sony A7R5) via separate ball with long clamp. For coarse orientation, I use the white light occasionally. Most of the time, for searching as well as for focusing, I have just the red light on (this proofed to be very useful, many critters, e.g. shrimps anf basketstars, are not able to perceive the red light)... Wolfgang

Hi Rich, As far as I know, "Hue" and "Saturation" of the water is nothing one can adjust at the camera (regarding the RAW file). The actual color of the water is adjusted in post, e.g. in LRc, via the "Temp" and "Tint" sliders and (within the range of your RGB signals) you can produce virtually any color you like... Similar with darker/lighter of water, what can be adjusted as you like in post (but exposure to the right by ISO, shutter and aperture is, of course prefereable as the starting point)... It is just the balance of #1.: "Temp"&"Tint" between foreground subject and water that you can adjust by choosing the strobe temperature (or, alternatively, making a mask of the foreground and of the water and adjust this separtely) and of #2. darker/lighter ("Exposure") between foreground subject and water that you sleect by strobe power (or, alternatively, making a mask of the foreground and of the water and adjust "Exposure" separately I am not quite sure what you mean with "nice blue water column". For me the blue of the water in your second example photo looks good, but this is certainly a matter of personal taste. Maybe you could post an example where you like the blue of the water, so that one can understand what your goal is? Here is an example of mine, from my last trip to the Maledives (I just returned yesterday). Conditions for water were difficult as there was only little light in approx. 30m at approx. 08:00 AM, mediocre visibility (approx. 15m) and cloudy sky. Sony A7R5, Canon 8-15mm f/4 fisheye with 2x Sony TC at 30mm; 1/160s; f/9; ISO 400, 2*HF-1 with 4500K diffusers. Probably you do not like these colors, but when you tell me what you like, I think I can adjust the water to any color you would like to see: Wolfgang

Rolling shutter may be the problem in A7R5 video. I personally never saw any distructing distortion of subjects in my, very few, A7R5 videos. Others can commend the video issue certainly better...

Hi Assist, I am proud owner of A7R5 for almost three years. This camera is perfect for me, but I am photocentric and do (almost) no video. Many here have A1 or A1II for both photo and video and seem pretty satisfied with this camera ... I am sure A75 is very good for both photo and video for many here (A7R5 is perfect for photo, but few would go for this camera for serious video). SInce you have A7CII, you can decide by yourself whether both photo and video fulfills your demands (A75 will be better in both, but I believe that there are NOT worlds inbetween. I think in case A7CII is not good enough, A75 will also not do it)... Besides this, outstanding UW-photos or UW- videos can be produced with any of the cameras you consider. They all have high technical quality and the person behind the camera is, by far, the rate limiting factor... Maybe you can get a used housing for your A7CII and just go UW to make photos and videos (and then decide whether with A75, A1II, A7CR etc. the results will be better). Besides this, switching between A7CR and A7CII looks sexy to me (but a photo that is not good with A7CII will not become better with A7CR and a video done badly with A7CR will not improve with A7CII)... Another consideration is the lenses. These may be more important than the camera itself. Which do you have and/or intend to use? Wolfgang

I have the Nitecore NL2153HP with 5300 mAh for my HF1's. After a full day of diving and making photos (I seldom use the videolight), I have still 60% -75% of charge available. No need for more capacity...

I remember correpondence with Backscatter where they wrote me that the flash will shut off, when used with batteries that do not allow to draw a minimum of current, like e.g. 20A... Who knows what the outcome could be when inserting different kind of batteries, some with, some without built in protection circuits (maybe of different kind)? A shut off of the flash might be the least problem... => I fear that beeing too stingy can cost a lot more money in the end (At least the price of purchasing multiple different batteries before buying the right ones; not to speak about broken equipment). At the best one could save a couple of Euros, by taking the risk. This is opposed by total costs of many thousands of Euros for the entire rig... Wolfgang

price reduction: 280 Euro

price reduction: Sony 90mm macro lens (new: 799 Euro): asking 450 Euro Focus gear (new: 220 Euro): asking 150 Euro Macroport 105 (new: 440 Euro): asking 290 Euro selling together as set for 850 Euro (preferred).

Hi Rich, Since you mention Tokina 10-17mm: It will be optimal for R7, but not for R6, since this as an APS-C type lens. I remember reports from people using the Tokina with FF cameras (it seems this lens has an extraordinary large image circle), but this is probably not the IQ you are expecting for spending $$$$s dollars for the entire rig... For FF you may want the Canon EF 8-15mm fisheye (or the new RF version) but these lenses are nor as flexible as the Tokina on APS-C (or on MFT (with 0.71x speedbooster)), they offer just switching from circular fisheye to 180° diagonal fisheye and back... Wolfgang

I do not recommend to buy a new housing for an old camera model. In the end you will want to upgrade soon and the used housing will not be worth much on the second hand market, since nobody wants the housing. Maybe you can get a second hand housing for R6 at a reasonable price. If not, it is more economical to buy both new housing and camera model (but camera model with latest technology). You will use the combination longer and also get a better price for the used housing, when you once upgrade...

I cannot help here, but I am wondering for what purpose this upgrade serves? Compatibility with type II extensions?? P.S.: Here I found the reasoning for this upgrade: https://www.seatech.co.nz/blogs/product-information-new-releases/nauticam-n120-port-adaptors-lock-mechanism-upgrade?srsltid=AfmBOooyQBblQAv47WZo8VCaB5ediSh_z5-Od3lE8k-gK-E7EASGpSjz

I got the Backscatter Sony flashtrigger that is able to trigger the HF-1 in HSS mode and tested out by myself (with Sony A7R5): When the "drive mode" is set to "slow" (3 fps), only every 4th image is lit by the strobe and the other three are black... => This means that drive mode is not working with HSS. The flash fires after every (approx.) 1.3s ... For fast sequences one has to remain in the regular "manual mode", within the limits of the flash sync. speed.

My personal experience with strobe service is extremely bad with Sea&Sea (Europe; located in Netherlands), time span was approx. 2-4 years ago: I had four total losses (YS-D2) and it was not possible to contact them or get any response from them, nether by telephone nor by EMail. The service is(was?) practically non existing... Completely different situation with Backscatter (just now): Two HF-1 had their electrodes corroded. Very fast response, quick and kind handling (although at present there are problems in sending items between US and Europe and the repaired flashes are, at present, delayed in the customs; this is, however, not Backscatters fault)... Wolfgang

I did not test for FF, but made comparisons between Nauticam 140mm and Zen DP100 for MFT (the tread is in the old forum). If existing, the differences were minor. Maybe for FF there is some improvement with 140mm domeport. More important for sharpness in the corners is probably the correct extension and stopping down,.. A clear advantage of the 140mm dome is, that one can put the lens together with the hood into the domport, while with DP100 one has to remove the hood. I believe this can improve IQ substantially, as this minimizes the stray light from the flashes falling into the optics (together with the hood on the domeport)... Wolfgang

Eizo coloredge is probably the best, but also the most expensive... I cannot compare to other high quality monitors for photographers since this is my first monitor of this kind, but my BenQ SW270c does what is expected from a monitor in this class. Approx. 1 year ago the monitor failed and I had to send it in for repair. It turned out repair is too elaborated (more or less a total loss), but they send me a refurbished replacement monitor (same model) for free on goodwill basis, although the warranty was already over since > 3 years. I can recommend this brand... Wolfgang

With the 2x TC the 8-15mm fisheye will become a 16-30mm fisheye (not 50mm)... According to calculations for equisolid fisheye, 16-30mm will be 170° - 85° diagonal angle of view (AOV). According to Nauticam's portcharts, the FCP-1 with Sony 28-60mm will give 170° - 74°, i.e. pretty similar AOVs... => I would say that the Canon 8-15mm & 2x Sony TC is some kind of "poor mans FCP" (it does not seem from the reviews, however, that FCP provides better IQ) Wolfgang

Interesting that both are nominally 4500K. In your side by side photo the Retra looks clearly cooler (but maybe the Kelvin designation refers to the output at the end and the spectrum of the Retra strobe is different to the HF-1)...

The flat diffuser from Backscatter that is on the Retra strobe seems to be the 4500K one. What color temperature does the Retra dome diffuser, mounted to the HF-1, have?